Anthracene derivative, and light emitting element, light emitting device, and electronic device using the anthracene derivative

ABSTRACT

It is an object to provide a noble anthracene derivative, a light emitting element with a high luminous efficiency, and further a light emitting element with a long lifetime. It is another object to provide a light emitting device and electronic device with a long lifetime by using the light emitting element. An anthracene derivative represented by General Formula (1) is provided. Since the anthracene derivative represented by General Formula (1) has a high luminous efficiency, when the anthracene derivative is used for a light emitting element, the light emitting element can have a high luminous efficiency. Further, when the anthracene derivative represented by General Formula (1) is used for a light emitting element, the light emitting element can have a long lifetime.

TECHNICAL FIELD

The present invention relates to anthracene derivatives, and a lightemitting element, a light emitting device, and an electronic devicewhich use the anthracene derivatives.

BACKGROUND ART

An organic compound can take various structures compared with aninorganic compound, and it is possible to synthesize a material havingvarious functions by appropriate molecular-design of an organiccompound. Owing to these advantages, photo electronics and electronicswhich employ a functional organic material have been attractingattention in recent years.

For example, a solar cell, a light emitting element, an organictransistor, and the like are exemplified as an electronic device usingan organic compound as a functional organic material. These devices takeadvantage of electrical properties and optical properties of the organiccompound. Among them, in particular, a light emitting element has beenmaking remarkable progress.

It is considered that the light emission mechanism of a light emittingelement is as follows: when a voltage is applied to a pair of electrodesbetween which a light emitting layer is interposed, electrons injectedfrom a cathode and holes injected from an anode are recombined at aluminescent center in the light emitting layer to form a molecularexciton, and energy is released to emit light when the molecular excitonreturns to the ground state. As excited states, a singlet excited stateand a triplet excited state are known, and light emission is consideredto be possible through either of these excited states.

In an attempt to improve the performances of such a light emittingelement, there are many problems which depend on the material, and inorder to solve these problems, improvement of the element structure anddevelopment of a material have been carried out.

As a material used for a light emitting element, anthracene derivativescan be given.

For example, Patent Document 1 (Japanese Published Patent ApplicationNo. 2003-142269) mentions an organic EL display which uses an anthracenederivative or the like as a host material of a red light emitting layer.

In addition, Patent Document 2 (PCT International Publication No.2006-049316) mentions an organic electroluminescent element which usesaromatic tertiary amine having an anthracene skeleton for a holeinjecting material.

As mentioned in Patent Document 1 and Patent Document 2, the anthracenederivatives are often used in light emitting elements. However, in orderto put a light emitting element to practical use, development of amaterial with more superior characteristics has been demanded.

DISCLOSURE OF INVENTION

In view of the foregoing problems, it is an object of the presentinvention to provide a novel anthracene derivative.

In addition, it is an object to provide a light emitting element with ahigh luminous efficiency and a light emitting element with a reduceddriving voltage. Another object is to provide a light emitting deviceand an electronic device each having reduced power consumption by usingthe light emitting element.

One feature of the present invention is an anthracene derivativerepresented by General Formula (1).

(In the formula, Ar¹ represents an aryl group having 6 to 25 carbonatoms; each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms; and A represents either of substituentsshown by General Formulae (1-2) and (1-3). In General Formulae (1-2) and(1-3), Ar²¹ represents an aryl group having 6 to 25 carbon atoms; R³¹represents any of a hydrogen atom, an alkyl group having 1 to 4 carbonatoms, and an aryl group having 6 to 25 carbon atoms; and R³² representsany of an alkyl group having 1 to 4 carbon atoms and an aryl grouphaving 6 to 25 carbon atoms. Ar³¹ represents an aryl group having 6 to25 carbon atoms; β represents an arylene group having 6 to 25 carbonatoms; and each of R⁴¹ and R⁴² represents any of a hydrogen atom, analkyl group having 1 to 4 carbon atoms, and an aryl group having 6 to 25carbon atoms.)

Another feature of the present invention is an anthracene derivativerepresented by General Formula (2).

(In the formula, Ar¹ represents an aryl group having 6 to 25 carbonatoms; each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms; and A represents either of substituentsshown by General Formulae (2-2) and (2-3). In General Formulae (2-2) and(2-3), Ar²¹ represents an aryl group having 6 to 25 carbon atoms; R³¹represents any of a hydrogen atom, an alkyl group having 1 to 4 carbonatoms, and an aryl group having 6 to 25 carbon atoms; and each of R³³ toR³⁷ represents any of a hydrogen atom, an alkyl group having 1 to 4carbon atoms, and an aryl group having 6 to 15 carbon atoms. Ar³¹represents an aryl group having 6 to 25 carbon atoms; each of R⁴¹ andR⁴² represents any of a hydrogen atom, an alkyl group having 1 to 4carbon atoms, and an aryl group having 6 to 25 carbon atoms; and each ofR⁴³ to R⁴⁶ represents a hydrogen atom, an alkyl group having 1 to 4carbon atoms, or an aryl group having 6 to 15 carbon atoms.)

Yet another feature of the present invention is an anthracene derivativerepresented by General Formula (3).

(In the formula, Ar¹ represents an aryl group having 6 to 25 carbonatoms; each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms; and A represents either of substituentsshown by General Formulae (3-2) and (3-3). In General Formulae (3-2) and(3-3), Ar²¹ represents an aryl group having 6 to 25 carbon atoms; R³¹represents any of a hydrogen atom, an alkyl group having 1 to 4 carbonatoms, and an aryl group having 6 to 25 carbon atoms; and Ar³¹represents an aryl group having 6 to 25 carbon atoms. Each of R⁴¹ andR⁴² represents any of a hydrogen atom, an alkyl group having 1 to 4carbon atoms, and an aryl group having 6 to 25 carbon atoms.)

Still another feature of the present invention is an anthracenederivative represented by General Formula (4).

(In the formula, Ar¹ represents an aryl group having 6 to 25 carbonatoms; each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms; and A represents either of substituentsshown by General Formulae (4-2) and (4-3). In General Formulae (4-2) and(4-3), Ar²¹ represents any of a phenyl group, a 1-naphthyl group, and a2-naphthyl group; R³¹ represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and Ar³¹ represents any of a phenyl group, a 1-naphthyl group,and a 2-naphthyl group. Each of R⁴¹ and R⁴² represents any of a hydrogenatom, an alkyl group having 1 to 4 carbon atoms, and an aryl grouphaving 6 to 25 carbon atoms.)

In the above structure, Ar¹ is preferably a substituent represented byGeneral Formula (11-1).

(Each of R¹¹ to R¹⁵ represents a hydrogen atom, an alkyl group having 1to 4 carbon atoms, or an aryl group having 6 to 15 carbon atoms.)

In the above structure, Ar¹ is preferably a substituent represented byStructural Formula (11-2) or (11-3).

In the above structure, Ar¹ is preferably a substituent represented byStructural Formula (11-4).

(In the formula, each of R¹⁶ and R¹⁷ represents an alkyl group having 1to 4 carbon atoms or a phenyl group.)

In the above structure, Ar¹ is preferably a substituent represented byStructural Formula (11-5) or (11-6).

One feature of the present invention is an anthracene derivativerepresented by General Formula (5).

(In the formula, each of R¹ to R⁸ represents a hydrogen atom or an alkylgroup having 1 to 4 carbon atoms; and A represents either ofsubstituents shown by General Formulae (5-2) and (5-3). In GeneralFormulae (5-2) and (5-3), Ar²¹ represents an aryl group having 6 to 25carbon atoms; R³¹ represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and R³² represents any of an alkyl group having 1 to 4 carbonatoms and an aryl group having 6 to 25 carbon atoms. Ar³¹ represents anaryl group having 6 to 25 carbon atoms; β represents an arylene grouphaving 6 to 25 carbon atoms; and each of R⁴¹ and R⁴² represents any of ahydrogen atom, an alkyl group having 1 to 4 carbon atoms, and an arylgroup having 6 to 25 carbon atoms.)

Another feature of the present invention is an anthracene derivativerepresented by General Formula (6).

(In the formula, each of R¹ to R⁸ represents a hydrogen atom or an alkylgroup having 1 to 4 carbon atoms; and A represents either ofsubstituents shown by General Formulae (6-2) and (6-3). In GeneralFormulae (6-2) and (6-3), Ar²¹ represents an aryl group having 6 to 25carbon atoms; R³¹ represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and each of R³³ to R³⁷ represents any of a hydrogen atom, analkyl group having 1 to 4 carbon atoms, and an aryl group having 6 to 15carbon atoms. Ar³¹ represents an aryl group having 6 to 25 carbon atoms;each of R⁴¹ and R⁴² represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and each of R⁴³ to R⁴⁶ represents a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, or an aryl group having 6 to 15 carbonatoms.)

One feature of the present invention is an anthracene derivativerepresented by General Formula (7).

(In the formula, each of R¹ to R⁸ represents a hydrogen atom or an alkylgroup having 1 to 4 carbon atoms; and A represents either ofsubstituents shown by General Formulae (7-2) and (7-3). In GeneralFormulae (7-2) and (7-3), Ar²¹ represents an aryl group having 6 to 25carbon atoms; R³¹ represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and Ar³¹ represents an aryl group having 6 to 25 carbon atoms.Each of R⁴¹ and R⁴² represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms.)

One feature of the present invention is an anthracene derivativerepresented by General Formula (8).

(In the formula, each of R¹ to R⁸ represents a hydrogen atom or an alkylgroup having 1 to 4 carbon atoms; and A represents either ofsubstituents shown by General Formulae (8-2) and (8-3). In GeneralFormulae (8-2) and (8-3), Ar²¹ represents any of a phenyl group, a1-naphthyl group, and a 2-naphthyl group; R³¹ represents any of ahydrogen atom, an alkyl group having 1 to 4 carbon atoms, and an arylgroup having 6 to 25 carbon atoms; and Ar³¹ represents any of a phenylgroup, a 1-naphthyl group, and a 2-naphthyl group. Each of R⁴¹ and R⁴²represents any of a hydrogen atom, an alkyl group having 1 to 4 carbonatoms, and an aryl group having 6 to 25 carbon atoms.)

Further, one feature of the present invention is a light emittingelement using any of the foregoing anthracene derivatives. Specifically,the feature of the present invention is a light emitting element havingthe anthracene derivative between a pair of electrodes.

Another feature of the present invention is a light emitting elementhaving a light emitting layer between a pair of electrodes, in which thelight emitting layer includes any of the above-described anthracenederivatives. It is particularly preferable to use any of theabove-mentioned anthracene derivatives as a light emitting substance.That is, it is preferable to have a structure in which the anthracenederivative emits light.

The light emitting device of the present invention possesses a lightemitting element which includes a layer including a light emittingsubstance between a pair of electrodes and in which the layer includinga light emitting substance includes any of the foregoing anthracenederivatives. The light emitting device of the present invention alsopossesses a controller for controlling light emission of the lightemitting element. The light emitting device in this specificationincludes an image display device, a light emitting device, and a lightsource (including a lighting device). Further, the light emitting devicealso includes all types of modules, e.g., a module in which a connectorsuch as an FPC (Flexible Printed Circuit), a TAB (Tape AutomatedBonding) tape, or a TCP (Tape Carrier Package) is attached to a panel, amodule in which a printed wiring board is provided at an end of a TABtape or a TCP, and a module in which an IC (Integrated Circuit) isdirectly mounted on the light emitting element by a COG (Chip On Glass)method.

Further, an electronic device using the light emitting element of thepresent invention in its display portion is also included in thecategory of the present invention. Therefore, the electronic device ofthe present invention has a display portion, and the display portion isequipped with the above-described light emitting element and thecontroller for controlling light emission of the light emitting element.

An anthracene derivative of the present invention emits lightefficiently. Therefore, by using the anthracene derivative of thepresent invention in a light emitting element, a light emitting elementwith a high luminous efficiency can be provided. Also, the anthracenederivative of the present invention is superior in a hole transportingproperty. Therefore, by using the anthracene derivative of the presentinvention in a light emitting element, a light emitting element with areduced driving voltage can be provided.

Further, by using an anthracene derivative of the present invention, alight emitting device and an electronic device with reduced powerconsumption can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIGS. 1A to 1C show light emitting elements according to the presentinvention;

FIG. 2 shows a light emitting element according to the presentinvention;

FIG. 3 shows a light emitting element according to the presentinvention;

FIGS. 4A and 4B show a light emitting device according to the presentinvention;

FIGS. 5A and 5B show a light emitting device according to the presentinvention;

FIGS. 6A to 6D show electronic devices according to the presentinvention;

FIG. 7 shows an electronic device according to the present invention;

FIG. 8 shows a lighting device according to the present invention;

FIG. 9 shows a lighting device according to the present invention;

FIGS. 10A and 10B show ¹H NMR charts ofN-phenyl-(9-phenyl-9H-carbazol-3-yl)amine (abbreviation: PCA);

FIG. 11 shows an absorption spectrum of a toluene solution of9-[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]-10-phenylanthracene(abbreviation: PCAPhA);

FIG. 12 shows an absorption spectrum of a thin film of9-[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]-10-phenylanthracene(abbreviation: PCAPhA);

FIG. 13 shows an emission spectrum of a toluene solution of9-[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]-10-phenylanthracene(abbreviation: PCAPhA);

FIG. 14 shows an emission spectrum of a thin film of9-[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]-10-phenylanthracene(abbreviation: PCAPhA);

FIG. 15 shows a CV measurement result of an oxidation side of9-[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]-10-phenylanthracene(abbreviation: PCAPhA);

FIG. 16 shows a CV measurement of a reduction side of9-[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]-10-phenylanthracene(abbreviation: PCAPhA);

FIGS. 17A and 17B show ¹H NMR charts of9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A);

FIG. 18 shows an absorption spectrum of a toluene solution of9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A);

FIG. 19 shows an absorption spectrum of a thin film of9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A);

FIG. 20 shows an emission spectrum of a toluene solution of9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A);

FIG. 21 shows an emission spectrum of a thin film of9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A);

FIG. 22 shows a CV measurement result of oxidation of9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A);

FIG. 23 shows a CV measurement of reduction of9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A);

FIGS. 24A and 24B show ¹H NMR charts of 4-(carbazol-9-yl)diphenylamine(abbreviation: YGA);

FIGS. 25A and 25B show ¹H NMR charts of9-{N-[4-(carbazol-9-yl)phenyl]-N-phenylamino}-10-phenylanthracene(abbreviation: YGAPhA);

FIG. 26 shows an absorption spectrum of a toluene solution of9-{N-[4-(carbazol-9-yl)phenyl]-N-phenylamino}-10-phenylanthracene(abbreviation: YGAPhA);

FIG. 27 shows an absorption spectrum of a thin film of9-{N-[4-(carbazol-9-yl)phenyl]-N-phenylamino}-10-phenylanthracene(abbreviation: YGAPhA);

FIG. 28 shows an emission spectrum of a toluene solution of9-{N-[4-(carbazol-9-yl)phenyl]-N-phenylamino}-10-phenylanthracene(abbreviation: YGAPhA);

FIG. 29 shows an emission spectrum of a thin film of9-{N-[4-(carbazol-9-yl)phenyl]-N-phenylamino}-10-phenylanthracene(abbreviation: YGAPhA);

FIGS. 30A and 30B show ¹H NMR charts of9,10-bis[N-(4-carbazol-9-yl)phenyl-N-phenylamino]anthracene(abbreviation: YGA2A);

FIG. 31 shows an absorption spectrum of a toluene solution of9,10-bis[N-(4-carbazol-9-yl)phenyl-N-phenylamino]anthracene(abbreviation: YGA2A);

FIG. 32 shows an absorption spectrum of a thin film of9,10-bis[N-(4-carbazol-9-yl)phenyl-N-phenylamino]anthracene(abbreviation: YGA2A);

FIG. 33 shows an emission spectrum of a toluene solution of9,10-bis[N-(4-carbazol-9-yl)phenyl-N-phenylamino]anthracene(abbreviation: YGA2A);

FIG. 34 shows an emission spectrum of a thin film of9,10-bis[N-(4-carbazol-9-yl)phenyl-N-phenylamino]anthracene(abbreviation: YGA2A);

FIG. 35 shows a light emitting element of examples;

FIG. 36 shows luminance-current density characteristics of a lightemitting element 1;

FIG. 37 shows luminance-voltage characteristics of the light emittingelement 1;

FIG. 38 shows current efficiency-luminance characteristics of the lightemitting element 1;

FIG. 39 shows an emission spectrum of the light emitting element 1;

FIG. 40 shows luminance-current density characteristics of a lightemitting element 2 and a light emitting element 3;

FIG. 41 shows luminance-voltage characteristics of the light emittingelement 2 and the light emitting element 3;

FIG. 42 shows current efficiency-luminance characteristics of the lightemitting element 2 and the light emitting element 3;

FIG. 43 shows emission spectra of the light emitting element 2 and thelight emitting element 3;

FIG. 44 shows time dependence of normalized luminance of the lightemitting element 2;

FIG. 45 shows luminance-current density characteristics of a lightemitting element 4 and a comparative light emitting element 5;

FIG. 46 shows luminance-voltage characteristics of the light emittingelement 4 and the comparative light emitting element 5;

FIG. 47 shows current efficiency-luminance characteristics of the lightemitting element 4 and the comparative light emitting element 5;

FIG. 48 shows emission spectra of the light emitting element 4 and thecomparative light emitting element 5;

FIG. 49 shows luminance-current density characteristics of the lightemitting element 6 and the comparative light emitting element 7;

FIG. 50 shows luminance-voltage characteristics of the light emittingelement 6 and the comparative light emitting element 7;

FIG. 51 shows current efficiency-luminance characteristics of the lightemitting element 6 and the comparative light emitting element 7;

FIG. 52 shows emission spectra of the light emitting element 6 and thecomparative light emitting element 7;

FIG. 53 shows a light emitting element of an example;

FIG. 54 shows luminance-current density characteristics of a lightemitting element 8 and a light emitting element 9;

FIG. 55 shows luminance-voltage characteristics of the light emittingelement 8 and the light emitting element 9;

FIG. 56 shows current efficiency-luminance characteristics of the lightemitting element 8 and the light emitting element 9; and

FIG. 57 shows emission spectra of the light emitting element 8 and thelight emitting element 9.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment modes and examples of the present invention will be describedin detail with reference to the drawings. It is easily understood bythose skilled in the art that various changes may be made in forms anddetails without departing from the spirit and the scope of theinvention. Therefore, the present invention should not be limited to thedescriptions of the embodiment modes and the examples below.

Embodiment Mode 1

Embodiment Mode 1 will describe an anthracene derivative of the presentinvention.

An anthracene derivative of the present invention has an amino grouphaving a 9-arylcarbazole skeleton in position 9 of the anthraceneskeleton and also has an aryl group in position 10 of the anthraceneskeleton. That is, the anthracene derivative of the present invention isan anthracene derivative represented by General Formula (1).

(In the formula, Ar¹ represents an aryl group having 6 to 25 carbonatoms; each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms; and A represents either of substituentsshown by General Formulae (1-2) and (1-3). In General Formulae (1-2) and(1-3), Ar²¹ represents an aryl group having 6 to 25 carbon atoms; R³¹represents any of a hydrogen atom, an alkyl group having 1 to 4 carbonatoms, and an aryl group having 6 to 25 carbon atoms; and R³² representsany of an alkyl group having 1 to 4 carbon atoms and an aryl grouphaving 6 to 25 carbon atoms. Ar³¹ represents an aryl group having 6 to25 carbon atoms; β represents an arylene group having 6 to 25 carbonatoms; and each of R⁴¹ and R⁴² represents any of a hydrogen atom, analkyl group having 1 to 4 carbon atoms, and an aryl group having 6 to 25carbon atoms.)

In General Formula (1), a substituent represented by Ar¹ is, forexample, any of substituents represented by Structural Formulae (20-1)to (20-9).

In General Formula (1-2), a substituent represented by Ar²¹ is, forexample, any of substituents represented by Structural Formulae (21-1)to (21-9).

In General Formula (1-2), a substituent represented by R³¹ is, forexample, any of substituents represented by Structural Formulae (22-1)to (22-18).

In General Formula (1-2), a substituent represented by R³² is, forexample, any of substituents represented by Structural Formulae (23-1)to (23-17).

Accordingly, the substituent represented by General Formula (1-2) is,for example, any of substituents represented by Structural Formulae(24-1) to (24-52).

Further, in General Formula (1-3), a substituent represented by Ar³¹ is,for example, any of substituents represented by Structural Formulae(31-1) to (31-9).

Further, in General Formula (1-3), a substituent represented by β is,for example, any of substituents represented by Structural Formulae(32-1) to (32-10).

In addition, in General Formula (1-3), each of substituents representedby R⁴¹ and R⁴² is, for example, any of substituents represented byStructural Formulae (33-1) to (33-18).

Accordingly, the substituent represented by General Formula (1-3) is,for example, any of substituents represented by Structural Formulae(34-1) to (34-35).

The anthracene derivative represented by General Formula (1) ispreferably an anthracene derivative represented by General Formula (2).

(In the formula, Ar¹ represents an aryl group having 6 to 25 carbonatoms; each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms; and A represents either of substituentsshown by General Formulae (2-2) and (2-3). In General Formulae (2-2) and(2-3), Ar²¹ represents an aryl group having 6 to 25 carbon atoms; R³¹represents any of a hydrogen atom, an alkyl group having 1 to 4 carbonatoms, and an aryl group having 6 to 25 carbon atoms; and each of R³³ toR³⁷ represents any of a hydrogen atom, an alkyl group having 1 to 4carbon atoms, and an aryl group having 6 to 15 carbon atoms. Ar³¹represents an aryl group having 6 to 25 carbon atoms; each of R⁴¹ andR⁴² represents any of a hydrogen atom, an alkyl group having 1 to 4carbon atoms, and an aryl group having 6 to 25 carbon atoms; and each ofR⁴³ to R⁴⁶ represents a hydrogen atom, an alkyl group having 1 to 4carbon atoms, or an aryl group having 6 to 15 carbon atoms.)

The anthracene derivative represented by General Formula (1) ispreferably an anthracene derivative represented by General Formula (3).

(In the formula, Ar¹ represents an aryl group having 6 to 25 carbonatoms; each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms; and A represents either of substituentsshown by General Formulae (3-2) and (3-3). In General Formulae (3-2) and(3-3), Ar²¹ represents an aryl group having 6 to 25 carbon atoms; R³¹represents any of a hydrogen atom, an alkyl group having 1 to 4 carbonatoms, and an aryl group having 6 to 25 carbon atoms; and Ar³¹represents an aryl group having 6 to 25 carbon atoms. Each of R⁴¹ andR⁴² represents any of a hydrogen atom, an alkyl group having 1 to 4carbon atoms, and an aryl group having 6 to 25 carbon atoms.)

The anthracene derivative represented by General Formula (1) ispreferably an anthracene derivative represented by General Formula (4).

(In the formula, Ar¹ represents an aryl group having 6 to 25 carbonatoms; each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms; and A represents either of substituentsshown by General Formulae (4-2) and (4-3). In General Formulae (4-2) and(4-3), Ar²¹ represents any of a phenyl group, a 1-naphthyl group, and a2-naphthyl group; R³¹ represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and Ar³¹ represents any of a phenyl group, a 1-naphthyl group,and a 2-naphthyl group. Each of R⁴¹ and R⁴² represents any of a hydrogenatom, an alkyl group having 1 to 4 carbon atoms, and an aryl grouphaving 6 to 25 carbon atoms.)

In the General Formulae (1) to (4), Ar¹ is preferably a substituentrepresented by General Formula (11-1).

(In the formula, each of R¹¹ to R¹⁵ represents any of a hydrogen atom,an alkyl group having 1 to 4 carbon atoms, and an aryl group having 6 to15 carbon atoms.)

In the above General Formulae (1) to (4), Ar¹ is preferably either ofsubstituents represented by Structural Formulae (11-2) and (11-3).

Further, in the above General Formulae (1) to (4), Ar¹ is preferably asubstituent represented by Structural Formula (11-4).

(In the formula, each of R¹⁶ and R¹⁷ represents an alkyl group having 1to 4 carbon atoms or a phenyl group.)

Further, in the above General Formulae (1) to (4), Ar¹ is preferablyeither of substituents represented by Structural Formulae (11-5) and(11-6).

In addition, an anthracene derivative of the present invention has anamino group having a 9-arylcarbazole skeleton in position 9 and position10 of the anthracene skeleton. That is, the anthracene derivative of thepresent invention is an anthracene derivative represented by GeneralFormula (5).

(In the formula, each of R¹ to R⁸ represents a hydrogen atom or an alkylgroup having 1 to 4 carbon atoms; and A represents either ofsubstituents shown by General Formulae (5-2) and (5-3). In GeneralFormulae (5-2) and (5-3), Ar²¹ represents an aryl group having 6 to 25carbon atoms; R³¹ represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and R³² represents any of an alkyl group having 1 to 4 carbonatoms and an aryl group having 6 to 25 carbon atoms. Ar³¹ represents anaryl group having 6 to 25 carbon atoms; β represents an arylene grouphaving 6 to 25 carbon atoms; and each of R⁴¹ and R⁴² represents any of ahydrogen atom, an alkyl group having 1 to 4 carbon atoms, and an arylgroup having 6 to 25 carbon atoms.)

In General Formula (5-2), a substituent represented by Ar²¹ is, forexample, any of the above-described substituents represented byStructural Formulae (21-1) to (21-9).

Further, in General Formula (5-2), a substituent represented by R³¹ is,for example, any of the above-described substituents represented byStructural Formulae (22-1) to (22-18).

In addition, in General Formula (5-2), a substituent represented by R³²is, for example, any of the above-described substituents represented byStructural Formulae (23-1) to (23-17).

Accordingly, the substituent represented by General Formula (5-2) is,for example, any of the above-described substituents represented byStructural Formulae (24-1) to (24-52).

In General Formula (5-3), a substituent represented by Ar³¹ is, forexample, any of the above-described substituents represented byStructural Formulae (31-1) to (31-9).

Further, in General Formula (5-3), a substituent represented by β is,for example, any of the above-described substituents represented byStructural Formulae (32-1) to (32-10).

In addition, in General Formula (5-3), each of substituents representedby R⁴¹ and R⁴² is, for example, any of the above-described substituentsrepresented by Structural Formulae (33-1) to (33-18).

Accordingly, the substituent represented by General Formula (5-3) is,for example, any of the above-described substituents represented byStructural Formulae (34-1) to (34-35).

The anthracene derivative represented by General Formula (5) ispreferably an anthracene derivative represented by General Formula (6).

(In the formula, each of R¹ to R⁸ represents a hydrogen atom or an alkylgroup having 1 to 4 carbon atoms; and A represents either ofsubstituents shown by General Formulae (6-2) and (6-3). In GeneralFormulae (6-2) and (6-3), Ar²¹ represents an aryl group having 6 to 25carbon atoms; R³¹ represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and each of R³³ to R³⁷ represents any of a hydrogen atom, analkyl group having 1 to 4 carbon atoms, and an aryl group having 6 to 15carbon atoms. Ar³¹ represents an aryl group having 6 to 25 carbon atoms;each of R⁴¹ and R⁴² represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and each of R⁴³ to R⁴⁶ represents a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, or an aryl group having 6 to 15 carbonatoms.)

Further, an anthracene derivative represented by General Formula (7) ispreferable.

(In the formula, each of R¹ to R⁸ represents a hydrogen atom or an alkylgroup having 1 to 4 carbon atoms; and A represents either ofsubstituents shown by General Formulae (7-2) and (7-3). In GeneralFormulae (7-2) and (7-3), Ar²¹ represents an aryl group having 6 to 25carbon atoms; R³¹ represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and Ar³¹ represents an aryl group having 6 to 25 carbon atoms.Each of R⁴¹ and R⁴² represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms.)

Further, an anthracene derivative represented by General Formula (8) ispreferable.

(In the formula, each of R¹ to R⁸ represents a hydrogen atom or an alkylgroup having 1 to 4 carbon atoms; and A represents either ofsubstituents shown by General Formulae (8-2) and (8-3). In GeneralFormulae (8-2) and (8-3), Ar²¹ represents any of a phenyl group, a1-naphthyl group, and a 2-naphthyl group; R³¹ represents any of ahydrogen atom, an alkyl group having 1 to 4 carbon atoms, and an arylgroup having 6 to 25 carbon atoms; and Ar³¹ represents any of a phenylgroup, a 1-naphthyl group, and a 2-naphthyl group. Each of R⁴¹ and R⁴²represents any of a hydrogen atom, an alkyl group having 1 to 4 carbonatoms, and an aryl group having 6 to 25 carbon atoms.)

As specific examples of the anthracene derivatives represented byGeneral Formula (1) or (5), anthracene derivatives represented byStructural Formulae (201) to (256) and Structural Formulae (301) to(348) can be given. However, the present invention is not limited tothese examples.

The anthracene derivatives represented by Structural Formulae (201) to(238) are specific examples of the case where A is represented byGeneral Formula (1-2) in General Formula (1), and the anthracenederivatives represented by Structural Formulae (301) to (334) arespecific examples of the case where A is represented by General Formula(1-3) in General Formula (1). The anthracene derivatives represented byStructural Formulae (239) to (256) are specific examples of the casewhere A is represented by General Formula (5-2) in General Formula (5),and the anthracene derivatives represented by Structural Formulae (335)to (348) are specific examples of the case where A is represented byGeneral Formula (5-3) in General Formula (5).

As a synthesizing method of an anthracene derivative of the presentinvention, various reactions can be applied. For example, an anthracenederivative of the present invention can be synthesized by any ofsynthesizing methods shown in Synthetic Schemes (A-1) to (A-9) below.

First, a carbazole derivative can be synthesized using the method shownin Synthetic Scheme (A-1) or (A-2).

As shown in Synthetic Scheme (A-1), a carbazole derivative (Compound A)is reacted with halogen or a halide such as N-bromosuccinimide (NBS),N-iodosuccinimide (NIS), bromine (Br₂), potassium iodide (KI), or iodine(I₂) to synthesize a 3-halide carbazole derivative (Compound B), andthen the 3-halide carbazole derivative (Compound B) is subjected to acoupling reaction with arylamine using metal such as copper, a metalcompound such as copper(I) iodide, or a metal catalyst such as apalladium catalyst (Pd catalyst), so that a carbazol-3-amine derivative(Compound C) can be obtained. In Synthetic Scheme (A-1), a halogenelement (X¹) is preferably iodine or bromine. R³¹ represents any of ahydrogen atom, an alkyl group having 1 to 4 carbon atoms, and an arylgroup having 6 to 25 carbon atoms. R³² represents an alkyl group having1 to 4 carbon atoms or an aryl group having 6 to 25 carbon atoms.Further, Ar²¹ represents an aryl group having 6 to 25 carbon atoms.

As shown in Synthetic Scheme (A-2), a carbazole derivative (Compound E)is reacted with a dihalide (Compound D) of an aromatic compound tosynthesize a N-(aryl halide)carbazole derivative (Compound F), and thenthe N-(aryl halide)carbazole derivative (Compound F) is subjected to acoupling reaction with arylamine using metal such as copper, a metalcompound such as copper(I) iodide, or a metal catalyst such as apalladium catalyst (Pd catalyst), so that a carbazole derivative(Compound G) can be obtained. In Synthetic Scheme (A-2), a halogenelement (X² and X³) of the dihalide of an aromatic compound ispreferably iodine or bromine. X² and X³ may be the same or differentfrom each other. Each of R⁴¹ and R⁴² represents any of a hydrogen atom,an alkyl group having 1 to 4 carbon atoms, and an aryl group having 6 to25 carbon atoms. β represents an arylene group having 6 to 25 carbonatoms. Ar³¹ represents an aryl group having 6 to 25 carbon atoms.

An anthracene derivative can be synthesized by the methods shown inSynthetic Schemes (A-3) to (A-5).

As shown in Synthetic Scheme (A-3), a 9-anthracene halide derivative(Compound H) is subjected to a coupling reaction with arylboronic acid(Compound I) using a palladium catalyst, so that a 9-arylanthracenederivative (Compound J) can be obtained. A boronic acid of thearylboronic acid (Compound I) may be protected by an alkyl group or thelike.

Next, as shown in Synthetic Scheme (A-4), the 9-arylanthracenederivative (Compound J) is halogenated, so that a 9-aryl-10-anthracenehalide derivative (Compound L) can be obtained. When bromination isconducted in the halogenation reaction, the bromination can be conductedusing bromine, N-bromosuccinimide (NBS), or the like. In the case whereiodination is conducted, the iodination can be conducted using iodine,orthoperiodic acid, potassium iodide, N-iodosuccinimide (NIS), or thelike.

Alternatively, the 9-aryl-10-anthracene halide derivative (Compound L)can also be synthesized by a method shown in Synthetic Scheme (A-5).Specifically, a 9,10-anthracene dihalide derivative (Compound K), inwhich carbon at position 9 and carbon at position 10 are halogenated, issubjected to a coupling reaction with the arylboronic acid (Compound I)using a palladium catalyst, so that the 9-aryl-10-anthracene halidederivative (Compound L) can be obtained. A boronic acid of thearylboronic acid (Compound I) may be protected by an alkyl group or thelike.

In Synthetic Scheme (A-3) to (A-5), Ar¹ represents an aryl group having6 to 25 carbon atoms, each of R¹ to R⁸ represents a hydrogen atom or analkyl group having 1 to 4 carbon atoms, and each of X⁴ to X⁶ representshalogen.

Next, as shown in Synthetic Scheme (A-6), the 9-aryl-10-anthracenehalide derivative (Compound L) obtained by Synthetic Schemes (A-3) to(A-5) is subjected to a coupling reaction with the carbazole derivative(Compound C) obtained by Synthetic Scheme (A-1) using metal such ascopper, a metal compound such as copper(I) iodide, or a metal catalystsuch as a palladium catalyst (Pd catalyst), so that an anthracenederivative represented by General Formula (1-2a) can be obtained. Theanthracene derivative represented by General Formula (1-2a) correspondsto the case where A is represented by General Formula (1-2) in GeneralFormula (1).

In Synthetic Scheme (A-6) and General Formula (1-2a), each of R¹ to R⁸represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms;X⁴ represents halogen; and Ar²¹ represents an aryl group having 6 to 25carbon atoms. R³¹ represents any of a hydrogen atom, an alkyl grouphaving 1 to 4 carbon atoms, and an aryl group having 6 to 25 carbonatoms; and R³² represents either of an alkyl group having 1 to 4 carbonatoms or an aryl group having 6 to 25 carbon atoms.

As shown in Synthetic Scheme (A-7), the 9-aryl-10-anthracene halidederivative (Compound L) is subjected to a coupling reaction with thecarbazole derivative (Compound G) obtained by Synthetic Scheme (A-2)using metal such as copper, a metal compound such as copper(I) iodide,or a metal catalyst such as a palladium catalyst (Pd catalyst), so thatan anthracene derivative represented by General Formula (1-3a) can beobtained. The anthracene derivative represented by General Formula(1-3a) corresponds to the case where A is represented by General Formula(1-3) in General Formula (1).

In Synthetic Scheme (A-7) and General Formula (1-3a), each of R¹ to R⁸represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms;X⁴ represents halogen; and Ar³¹ represents an aryl group having 6 to 25carbon atoms. β represents an arylene group having 6 to 25 carbon atoms;and each of R⁴¹ and R⁴² represents any of a hydrogen atom, an alkylgroup having 1 to 4 carbon atoms, and an aryl group having 6 to 25carbon atoms.

As shown in Synthetic Scheme (A-8), the 9,10-anthracene dihalidederivative (Compound K) is subjected to a coupling reaction with thecarbazole derivative (Compound C) obtained by Synthetic Scheme (A-1)using metal such as copper, a metal compound such as copper(I) iodide,or a metal catalyst such as a palladium catalyst (Pd catalyst), so thatan anthracene derivative represented by General Formula (5-2a) can beobtained. The anthracene derivative represented by General Formula(5-2a) corresponds to the case where A is represented by General Formula(5-2) in General Formula (5).

In Synthetic Scheme (A-8) and General Formula (5-2a), each of R¹ to R⁸represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms;each of X⁴ and X⁵ represents halogen; and Ar²¹ represents an aryl grouphaving 6 to 25 carbon atoms. R³¹ represents any of a hydrogen atom, analkyl group having 1 to 4 carbon atoms, and an aryl group having 6 to 25carbon atoms; and R³² represents either of an alkyl group having 1 to 4carbon atoms or an aryl group having 6 to 25 carbon atoms.

As shown in Synthetic Scheme (A-9), the 9,10-anthracene dihalidederivative (Compound K) is subjected to a coupling reaction with thecarbazole derivative (Compound G) obtained by Synthetic Scheme (A-2)using metal such as copper, a metal compound such as copper(I) iodide,or a metal catalyst such as a palladium catalyst (Pd catalyst), so thatan anthracene derivative represented by General Formula (5-3a) can beobtained. The anthracene derivative represented by General Formula(5-3a) corresponds to the case where A is represented by General Formula(5-3) in General Formula (5).

In Synthetic Scheme (A-9) and General Formula (5-3a), each of R¹ to R⁸represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms;each of X⁴ and X⁵ represents halogen; and Ar³¹ represents an aryl grouphaving 6 to 25 carbon atoms. β represents an arylene group having 6 to25 carbon atoms; and each of R⁴¹ and R⁴² represents any of a hydrogenatom, an alkyl group having 1 to 4 carbon atoms, and an aryl grouphaving 6 to 25 carbon atoms.

The synthesizing method of an anthracene derivative of the presentinvention is not limited to the above-described methods, and theanthracene derivative can be synthesized by various methods.

The anthracene derivative of the present invention emits visible lightefficiently. In particular, light of green to red can be obtainedefficiently. Therefore, the anthracene derivative of the presentinvention can favorably be used in a light emitting element.

The anthracene derivative of the present invention is stable even whenoxidation and reduction reactions are repeated. Therefore, when theanthracene derivative of the present invention is used for a lightemitting element, the light emitting element can have a long lifetime.

Further, the anthracene derivative of the present invention emitsvisible light efficiently. Thus, when the anthracene derivative is usedin a light emitting element, the light emitting element can have a highluminous efficiency.

Since the anthracene derivative of the present invention emits visiblelight efficiently, a light emitting element with reduced powerconsumption can be provided.

Furthermore, the anthracene derivative of the present invention has acarbazole skeleton. A carbazole derivative is superior in heatresistance to a diphenylamine derivative, which has a similar moleculestructure to the carbazole derivative. Therefore, when the anthracenederivative of the present invention is used in a light emitting element,the light emitting element can have high heat resistance.

In the case where a film of the anthracene derivative of the presentinvention is formed by an evaporation method, the evaporation rate canbe easily controlled. Therefore, the anthracene derivative of thepresent invention can favorably be used in a light emitting element.

Embodiment Mode 2

One mode of a light emitting element using an anthracene derivative ofthe present invention will be described below with reference to FIG. 1A.

A light emitting element of the present invention has a plurality oflayers between a pair of electrodes. The plurality of layers is acombination of layers formed of a substance having a high carrierinjecting property and a substance having a high carrier transportingproperty which are stacked so that a light emitting region is formed ina place away from the electrodes, that is, recombination of carriers isperformed in an area away from the electrodes.

In this embodiment mode, a light emitting element includes a firstelectrode 102; a first layer 103, a second layer 104, a third layer 105,and a fourth layer 106 which are sequentially stacked over the firstelectrode 102; and a second electrode 107 provided thereover. It is tobe noted that description will be made below in this embodiment modewith an assumption that the first electrode 102 functions as an anodeand the second electrode 107 functions as a cathode.

A substrate 101 is used as a support of the light emitting element. Forthe substrate 101, glass, plastic, or the like can be used, for example.It is to be noted that another material may be used as long as itfunctions as a support in a manufacturing process of the light emittingelement.

For the first electrode 102, a metal, an alloy, an electricallyconductive compound, a mixture thereof, or the like having a high workfunction (specifically, 4.0 eV or more) is preferably used.Specifically, indium oxide-tin oxide (ITO: Indium Tin Oxide), indiumoxide-tin oxide including silicon or silicon oxide, indium oxide-zincoxide (IZO: Indium Zinc Oxide), indium oxide including tungsten oxideand zinc oxide (IWZO), or the like can be used, for example. Althoughthese conductive metal oxide films are generally formed by sputtering,they may be formed by applying a sol-gel method or the like. Forexample, a film of indium oxide-zinc oxide (IZO) can be formed by asputtering method using a target in which 1 to 20 wt % of zinc oxide isadded to indium oxide. A film of indium oxide including tungsten oxideand zinc oxide (IWZO) can be formed by a sputtering method using atarget in which 0.5 to 5 wt % of tungsten oxide and 0.1 to 1 wt % ofzinc oxide are included in indium oxide. In addition, gold (Au),platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum(Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), a nitride ofa metal material (such as titanium nitride), or the like is exemplified.

The first layer 103 is a layer including a substance having a high holeinjecting property. Molybdenum oxide, vanadium oxide, ruthenium oxide,tungsten oxide, manganese oxide, or the like can be used. Alternatively,the first layer 103 can be formed using phthalocyanine (abbreviation:H₂Pc); a phthalocyanine-based compound such as copper phthalocyanine(CuPc); an aromatic amine compound such as4,4′-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation:DPAB) or4,4′-bis(N-{4-[N-(3-methylphenyl)-N-phenylamino]phenyl}-N-phenylamino)biphenyl(abbreviation: DNTPD); a high molecular material such aspoly(3,4-ethylene dioxythiophene)/poly(styrenesulfonic acid)(PEDOT/PSS); or the like.

Alternatively, a composite material formed by composition of an organiccompound and an inorganic compound can be used for the first layer 103.In particular, a composite material including an organic compound and aninorganic compound having an electron accepting property with respect tothe organic compound has excellent hole injecting property and holetransporting property because the electron transfer takes place betweenthe organic compound and the inorganic compound, increasing the carrierdensity.

In a case of using a composite material formed by composition of anorganic compound and an inorganic compound for the first layer 103, thefirst layer 103 can achieve an ohmic contact with the first electrode102; therefore, the material of the first electrode 102 can be selectedregardless of work function.

As the inorganic compound used for the composite material, an oxide of atransition metal is preferably used. Further, oxides of metals belongingto Groups 4 to 8 in the periodic table can be given. Specifically, it ispreferable to use vanadium oxide, niobium oxide, tantalum oxide,chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, andrhenium oxide because of their high electron accepting properties. Amongthem, molybdenum oxide is particularly preferable because it is stableunder air, has a low moisture absorption property, and is easilyhandled.

As the organic compound used for the composite material, variouscompounds such as an aromatic amine compound, a carbazole derivative, anaromatic hydrocarbon, and a high molecular compound (such as oligomer,dendrimer, or polymer) can be used. The organic compound used for thecomposite material is preferably an organic compound having a high holetransporting property. Specifically, a substance having a hole mobilityof greater than or equal to 10⁻⁶ cm²/Vs is preferably used. However,other materials than these materials may also be used as long as thehole transporting properties thereof are higher than the electrontransporting properties thereof. The organic compounds which can be usedfor the composite material will be specifically described below.

For example, the following can be given as the aromatic amine compound:N,N′-di(p-tolyl)-N,N′-diphenyl-p-phenylenediamine (abbreviation:DTDPPA); 4,4′-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl(abbreviation: DPAB);4,4′-bis(N-{4-[N′-(3-methylphenyl)-N′-phenylamino]phenyl}-N-phenylamino)biphenyl(abbreviation: DNTPD);1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene(abbreviation: DPA3B); and the like.

As the carbazole derivative which can be used for the compositematerial, the following can be given specifically:3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole(abbreviation: PCzPCA1);3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole(abbreviation: PCzPCA2);3-[N-(1-naphtyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole(abbreviation: PCzPCN1); and the like.

Moreover, as the carbazole derivative which can be used for thecomposite material, the following can be given:4,4′-di(N-carbazolyl)biphenyl (abbreviation: CBP);1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB);9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA);1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene; and thelike.

As the aromatic hydrocarbon which can be used for the compositematerial, the following can be given for example:2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA);2-tert-butyl-9,10-di(1-naphthyl)anthracene;9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA);2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA);9,10-di(2-naphthyl)anthracene (abbreviation: DNA);9,10-diphenylanthracene (abbreviation: DPAnth); 2-tert-butylanthracene(abbreviation: t-BuAnth); 9,10-bis(4-methyl-1-naphthyl)anthracene(abbreviation: DMNA);2-tert-butyl-9,10-bis[2-(1-naphthyl)phenyl]anthracene;9,10-bis[2-(1-naphthyl)phenyl]anthracene;2,3,6,7-tetramethyl-9,10-di(1-naphthyl)anthracene;2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene; 9,9′-bianthryl;10,10′-diphenyl-9,9′-bianthryl;10,10′-bis(2-phenylphenyl)-9,9′-bianthryl;10,10′-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9′-bianthryl; anthracene;tetracene; rubrene; perylene; 2,5,8,11-tetra(tert-butyl)perylene; andthe like. Besides these compounds, pentacene, coronene, or the like canalso be used. Thus, an aromatic hydrocarbon which has a hole mobility ofgreater than or equal to 1×10⁻⁶ cm²/Vs and which has 14 to 42 carbonatoms is more preferable.

The aromatic hydrocarbon which can be used for the composite materialmay have a vinyl skeleton. As the aromatic hydrocarbon having a vinylgroup, the following are given for example:4,4′-bis(2,2-diphenylvinyl)biphenyl (abbreviation: DPVBi);9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene (abbreviation: DPVPA);and the like.

Moreover, a high molecular compound such as poly(N-vinylcarbazole)(abbreviation: PVK) or poly(4-vinyltriphenylamine) (abbreviation: PVTPA)can also be used.

As a substance forming the second layer 104, a substance having a highhole transporting property, specifically, an aromatic amine compound(that is, a compound having a benzene ring-nitrogen bond) is preferable.As a material that is widely used,4,4′-bis[N-(3-methylphenyl)-N-phenylamino]biphenyl, a derivativethereof, that is 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl(hereinafter referred to as NPB), and star burst aromatic aminecompounds such as 4,4′,4″-tris(N,N-diphenyl-amino)triphenylamine and4,4′,4″-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine can begiven. These materials described here are mainly substances each havinga hole mobility of greater than or equal to 10⁻⁶ cm²/Vs. However, othermaterials than these compounds may also be used as long as the holetransporting properties thereof are higher than the electrontransporting properties. The second layer 104 is not limited to a singlelayer, and a mixed layer of the aforementioned substances, or a stackedlayer which includes two or more layers each including theaforementioned substance may be used.

The third layer 105 is a layer including a light emitting substance. Inthis embodiment mode, the third layer 105 includes the anthracenederivative of the present invention described in Embodiment Mode 1. Theanthracene derivative of the present invention can favorably be appliedto a light emitting element as a light emitting substance since theanthracene derivative of the present invention exhibits light emissionof visible light.

As the fourth layer 106, a substance having a high electron transportingproperty can be used. For example, a layer including a metal complex orthe like having a quinoline or benzoquinoline skeleton, such astris(8-quinolinolato)aluminum (abbreviation: Alq),tris(4-methyl-8-quinolinolato)aluminum (abbreviation: Almq₃),bis(10-hydroxybenzo[h]quinolinato)beryllium (abbreviation: BeBq₂), orbis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum (abbreviation:BAlq) can be used. Alternatively, a metal complex or the like having anoxazole-based or thiazole-based ligand, such asbis[2-(2-hydroxyphenyl)benzoxazolato]zinc (abbreviation: Zn(BOX)₂) orbis[2-(2-hydroxyphenyl)benzothiazolato]zinc (abbreviation: Zn(BTZ)₂) canbe used. Besides the metal complexes,2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation:PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene(abbreviation: OXD-7),3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole(abbreviation: TAZ), bathophenanthroline (abbreviation: BPhen),bathocuproine (abbreviation: BCP), or the like can also be used. Thesubstances described here are mainly substances each having an electronmobility of greater than or equal to 10⁻⁶ cm²/Vs. The electrontransporting layer may be formed using other materials than thosedescribed above as long as the materials have higher electrontransporting properties than hole transporting properties. Furthermore,the electron transporting layer is not limited to a single layer, andtwo or more layers in which each layer is made of the aforementionedmaterial may be stacked.

As a substance forming the second electrode 107, a metal, an alloy, anelectrically conductive compound, a mixture thereof, or the like havinga low work function (specifically, 3.8 eV or less) is preferably used.As a specific example of such a cathode material, an element belongingto Group 1 or Group 2 in the periodic table, that is, an alkali metalsuch as lithium (Li) or cesium (Cs), an alkaline earth metal such asmagnesium (Mg), calcium (Ca), or strontium (Sr), or an alloy includingthese metals (MgAg, AlLi) can be employed. A rare earth metal such aseuropium (Eu) or ytterbium (Yb), an alloy including these rare earthmetals, or the like is also suitable. However, by providing a layerhaving a function to promote electron injection between the secondelectrode 107 and the fourth layer 106 so as to stack on the secondelectrode 107, various conductive materials such as Al, Ag, ITO, or ITOincluding silicon or silicon oxide can be used for the second electrode107 regardless of the magnitude of the work function.

For the layer having a function of promoting electron injection, analkali metal, an alkaline earth metal, or a compound thereof such aslithium fluoride (LiF), cesium fluoride (CsF), or calcium fluoride(CaF₂) can be used. For example, a layer which contains substance havingan electron transporting property and further includes an alkali metal,an alkaline earth metal, or a compound thereof such as a layer of Alqincluding magnesium (Mg) for example, can be used. It is preferable touse such a layer as the electron injecting layer since electroninjection from the second electrode 107 proceeds efficiently.

Various methods can be used for forming the first layer 103, the secondlayer 104, the third layer 105, and the fourth layer 106. For example,an evaporation method, an ink-jet method, a spin coating method, or thelike may be used. Furthermore, each electrode or each layer may beformed by a different film formation method.

By difference in potential between the first electrode 102 and thesecond electrode 107 in the light emitting element having theabove-described structure of the present invention, current flows andholes and electrons are recombined in the third layer 105 including asubstance with a high light emitting property, which results in lightemission. That is, the light emitting element of the present inventionhas a structure in which a light emitting region is formed in the thirdlayer 105.

Light emission is extracted outside through one or both of the firstelectrode 102 and the second electrode 107. Therefore, one or both ofthe first electrode 102 and the second electrode 107 has/have a lighttransmitting property. In the case where only the first electrode 102has a light transmitting property, light emission is extracted from asubstrate side through the first electrode 102 as shown in FIG. 1A. Inthe case where only the second electrode 107 has a light transmittingproperty, light emission is extracted from the side opposite to thesubstrate through the second electrode 107 as shown in FIG. 1B. In thecase where both of the first electrode 102 and the second electrode 107have a light transmitting property, light emission is extracted fromboth of the substrate side and the side opposite to the substratethrough the first electrode 102 and the second electrode 107, as shownin FIG. 1C.

A structure of layers provided between the first electrode 102 and thesecond electrode 107 is not limited to the above-described structure. Astructure other than the above-described structure may be used as longas the light emitting region, in which holes and electrons arerecombined, is located away from the first electrode 102 and the secondelectrode 107, which prevents quenching caused by adjacence of the lightemitting region and the metal.

In other words, a stacked structure of the layers is not strictlylimited to the above-mentioned structure, and a layer formed using asubstance having a high electron transporting property, a substancehaving a high hole transporting property, a substance having a highelectron injecting property, a substance having a high hole injectingproperty, a bipolar substance (substance having a high electrontransporting property and a high hole transporting property), a holeblocking material, or the like may be freely combined with theanthracene derivative of the present invention.

A light emitting element shown in FIG. 2 has a structure in which afirst electrode 302 serving as a cathode, a first layer 303 formed usinga substance having a high electron transporting property, a second layer304 including a light emitting substance, a third layer 305 formed usinga substance having a high hole transporting property, a fourth layer 306formed using a substance having a high hole injecting property, and asecond electrode 307 serving as an anode are sequentially stacked over asubstrate 301.

In this embodiment mode, a light emitting element is manufactured over asubstrate made of glass, plastic, or the like. By manufacturing aplurality of such light emitting elements described above over onesubstrate, a passive matrix type light emitting device can bemanufactured. Alternatively, for example, a thin film transistor (TFT)may be formed over a substrate made of glass, plastic, or the like, anda light emitting element may be manufactured so as to be connected tothe TFT electrically. Accordingly, an active matrix light emittingdevice can be manufactured, in which driving of the light emittingelement is controlled by the TFT. The structure of the TFT is notparticularly limited, and the TFT may be a staggered TFT or an inverselystaggered TFT. Crystallinity of a semiconductor used for the TFT is notparticularly limited as well, and an amorphous semiconductor or acrystalline semiconductor may be used. In addition, a driving circuitformed over a TFT substrate may be formed using an N-type TFT and aP-type TFT, or may be formed using one of an N-type TFT and a P-typeTFT.

Since the anthracene derivative of the present invention exhibits lightemission of visible light, the anthracene derivative can be used for alight emitting layer without being added with any other light emittingsubstance, as shown in this embodiment mode.

Since the anthracene derivative of the present invention has a highluminous efficiency, a light emitting element with a high luminousefficiency can be obtained by using the anthracene derivative in a lightemitting element. In addition, since the anthracene derivative of thepresent invention has an excellent hole transporting property, by usingthe anthracene derivative in a light emitting element, a light emittingelement with a reduced driving voltage can be obtained.

Embodiment Mode 3

In Embodiment Mode 3, a light emitting element having a differentstructure from that described in Embodiment Mode 2 will be described.

The third layer 105 described in Embodiment Mode 2 is formed bydispersing an anthracene derivative of the present invention intoanother substance, whereby light emission can be obtained from theanthracene derivative of the present invention. Since the anthracenederivative of the present invention exhibits light emission of visiblelight, a light emitting element exhibiting light emission of visiblelight can be obtained.

Here, various materials can be used as a substance in which theanthracene derivative of the present invention is dispersed. In additionto the substance having a high hole transporting property and thesubstance having a high electron transporting property, which aredescribed in Embodiment Mode 2, 4,4′-bis(N-carbazolyl)-biphenyl(abbreviation: CBP),2,2′,2″-(1,3,5-benzenetri-yl)-tris[1-phenyl-1H-benzimidazole](abbreviation: TPBI), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA),2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA),9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA), andthe like are exemplified.

Since the anthracene derivative of the present invention has a highluminous efficiency, a light emitting element with a high luminousefficiency can be obtained by using the anthracene derivative in a lightemitting element. In addition, since the anthracene derivative of thepresent invention has an excellent hole transporting property, by usingthe anthracene derivative of the present invention in a light emittingelement, a light emitting element with a reduced driving voltage can beobtained.

Regarding the layers other than the third layer 105, the structuredescribed in Embodiment Mode 2 can be appropriately used.

Embodiment Mode 4

In Embodiment Mode 4, a light emitting element with a structuredifferent from the structures described in Embodiment Modes 2 and 3 willbe described.

The third layer 105 described in Embodiment Mode 2 is formed bydispersing a light emitting substance in the anthracene derivative ofthe present invention, whereby light emission from the light emittingsubstance can be obtained.

In the case where the anthracene derivative of the present invention isused as a material in which another light emitting substance isdispersed, a light emission color derived from the light emittingsubstance can be obtained. Further, a mixed color resulted from theanthracene derivative of the present invention and the light emittingsubstance dispersed in the anthracene derivative can also be obtained.

Here, various materials can be used as a light emitting substancedispersed in the anthracene derivative of the present invention.Specifically, a fluorescent substance that emits fluorescence such as4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran(abbreviation: DCM1),4-(dicyanomethylene)-2-methyl-6-(julolidine-4-yl-vinyl)-4H-pyran(abbreviation: DCM2), N,N-dimethylquinacridone (abbreviation: DMQd), orrubrene can be used. Further, a phosphorescent substance that emitsphosphorescence such as(acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III)(abbreviation: Ir(Fdpq)₂(acac)),2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrinplatinum(II)(abbreviation: PtOEP), or the like can be used.

Regarding the layers other than the third layer 105, the structuredescribed in Embodiment Mode 2 can be appropriately used.

Embodiment Mode 5

In Embodiment Mode 5, a light emitting element with a structuredifferent from the structures described in Embodiment Modes 2 and 3 willbe described.

An anthracene derivative of the present invention has an excellent holetransporting property. Therefore, a layer including the anthracenederivative of the present invention can be provided between the anodeand the light emitting layer. Specifically, the anthracene derivative ofthe present invention can be used in the first layer 103 or the secondlayer 104 described in Embodiment Mode 1.

Also, in a case of applying the anthracene derivative of the presentinvention for the first layer 103, it is preferable to use as acomposite material the anthracene derivative of the present inventionand an inorganic compound having an electron accepting property withrespect to the anthracene derivative of the present invention. By usingsuch a composite material, carrier density increases, which contributesto improvement of the hole injecting property and the hole transportingproperty. Also, in a case of using the composite material for the firstlayer 103, the first layer 103 can achieve an ohmic contact with thefirst electrode 102; therefore, a material of the first electrode 102can be selected regardless of work function.

As the inorganic compound used for the composite material, an oxide of atransition metal is preferably used. Moreover, oxides of metalsbelonging to Groups 4 to 8 in the periodic table can be used.Specifically, it is preferable to use vanadium oxide, niobium oxide,tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide,manganese oxide, and rhenium oxide, because of their high electronaccepting properties. Among them, molybdenum oxide is preferable becauseit is stable under air, has a low moisture absorption property, and iseasily handled.

Note that this embodiment mode can be appropriately combined with any ofthe other embodiment modes.

Embodiment Mode 6

In Embodiment Mode 6, a light emitting element in which a plurality oflight emitting units according to the present invention is stacked(hereinafter, referred to as a stacked type element) will be describedwith reference to FIG. 3. This light emitting element is a lightemitting element that has a plurality of light emitting units between afirst electrode and a second electrode.

In FIG. 3, a first light emitting unit 511 and a second light emittingunit 512 are stacked between a first electrode 501 and a secondelectrode 502. An electrode similar to that described in Embodiment Mode2 can be applied to the first electrode 501 and the second electrode502. The first light emitting unit 511 and the second light emittingunit 512 may have the same structure or different structures, and astructure similar to those described in Embodiment Modes 2 to 5 can beapplied.

A charge generation layer 513 includes a composite material of anorganic compound and metal oxide. The composite material of an organiccompound and metal oxide is the composite material described inEmbodiment Mode 2 or 5, and includes an organic compound and metal oxidesuch as V₂O₅, MoO₃, or WO₃. As the organic compound, various compoundssuch as an aromatic amine compound, a carbazole derivative, aromatichydrocarbon, and a high molecular compound (oligomer, dendrimer,polymer, or the like) can be used. An organic compound having a holemobility of greater than or equal to 10⁻⁶ cm²/Vs is preferably appliedas the hole transporting organic compound. However, other substancesthan these compounds may also be used as long as the hole transportingproperties thereof are higher than the electron transporting propertiesthereof. The composite material of an organic compound and metal oxideis superior in carrier injecting property and carrier transportingproperty; therefore, low-voltage driving and low-current driving can berealized.

It is to be noted that the charge generation layer 513 may be formedwith a combination of a composite material of an organic compound andmetal oxide and another material. For example, the charge generationlayer 513 may be formed with a combination of a layer including thecomposite material of an organic compound and metal oxide and a layerincluding one compound selected from electron donating substances and acompound having a high electron transporting property. Further, thecharge generation layer 513 may be formed with a combination of a layerincluding the composite material of an organic compound and metal oxideand a transparent conductive film.

In any case, the charge generation layer 513, which is interposedbetween the first light emitting unit 511 and the second light emittingunit 512, is acceptable as long as electrons are injected to one of thelight emitting units and holes are injected to the other of the lightemitting units when a voltage is applied to the first electrode 501 andthe second electrode 502.

In this embodiment mode, the light emitting element having two lightemitting units is described; however, the present invention can beapplied similarly to a light emitting element in which three or morelight emitting units are stacked. By arranging a plurality of lightemitting units between a pair of electrodes in such a manner that theplurality of light emitting units is partitioned with a chargegeneration layer as in the light emitting element of this embodimentmode, a long-life element which emits light at a high luminance and alow current density, can be realized. When the light emitting element isapplied to a lighting device, since voltage drop owing to resistance ofthe electrode material can be small, uniform light emission from a largearea is possible. Further, a light emitting device capable oflow-voltage driving and low-power consumption can be realized.

This embodiment mode can be appropriately combined with any of the otherembodiment modes.

Embodiment Mode 7

In Embodiment Mode 7, a light emitting device manufactured using ananthracene derivative of the present invention will be described.

In this embodiment mode, a light emitting device manufactured using theanthracene derivative of the present invention will be described withreference to FIGS. 4A and 4B. FIG. 4A is a top view showing a lightemitting device, and FIG. 4B is a cross-sectional view of FIG. 4A takenalong lines A-A′ and B-B′. A driver circuit portion (source side drivercircuit) 601, a pixel portion 602, and a driver circuit portion (gateside driver circuit) 603, which are indicated by dotted lines, areincluded to control light emission of a light emitting element in thislight emitting device. In addition, a sealing substrate and a sealingmaterial are denoted by reference numerals 604 and 605, respectively,and a portion surrounded by the sealing material 605 corresponds to aspace 607.

A leading wiring 608 is a wiring for transmitting a signal to be inputto the source side driver circuit 601 and the gate side driver circuit603, and this wiring 608 receives a video signal, a clock signal, astart signal, a reset signal, and the like from an FPC (flexible printedcircuit) 609 that is an external input terminal. It is to be noted thatonly the FPC is shown here; however, the FPC may be provided with aprinted wiring board (PWB). The light emitting device in thisspecification includes not only a light emitting device itself but alsoa light emitting device attached with an FPC or a PWB.

Next, a cross-sectional structure will be described with reference toFIG. 4B. The driver circuit portion and the pixel portion are formedover an element substrate 610. Here, the source side driver circuit 601,which is the driver circuit portion, and one pixel in the pixel portion602 are shown.

A CMOS circuit which is a combination of an n-channel TFT 623 and ap-channel TFT 624 is formed as the source side driver circuit 601. Thedriver circuit may be formed using various circuits such as a CMOScircuit, a PMOS circuit, and an NMOS circuit. A driver-integration typedevice, in which a driver circuit is formed over a substrate over whicha pixel portion is also formed, is described in this embodiment mode;however, a driver circuit is not necessarily formed over a substrate,over which a pixel portion is formed, and can be formed outside thesubstrate.

The pixel portion 602 has a plurality of pixels, each of which includesa switching TFT 611, a current controlling TFT 612, and a firstelectrode 613 which is electrically connected to a drain of the currentcontrolling TFT 612. It is to be noted that an insulator 614 is formedso as to cover an end portion of the first electrode 613. Here, apositive photosensitive acrylic resin film is used for the insulator614.

The insulator 614 is formed so as to have a curved surface havingcurvature at an upper end portion or a lower end portion thereof inorder to obtain favorable coverage. For example, in a case of usingpositive photosensitive acrylic resin as a material for the insulator614, the insulator 614 is preferably formed so as to have a curvedsurface with a curvature radius (0.2 μm to 3 μm) only at the upper endportion thereof. Either a negative type resin which becomes insoluble inan etchant by photo-irradiation or a positive type resin which becomessoluble in an etchant by photo-irradiation can be used for the insulator614.

A layer 616 including a light emitting substance and a second electrode617 are formed over the first electrode 613. Here, a material having ahigh work function is preferably used as a material for the firstelectrode 613 serving as an anode. For example, the first electrode 613can be formed by using stacked layers of a titanium nitride film and afilm including aluminum as its main component; a three-layer structureof a titanium nitride film, a film including aluminum as its maincomponent, and a titanium nitride film; or the like as well as asingle-layer film such as an ITO film, an indium tin oxide filmincluding silicon, an indium oxide film including 2 to 20 wt % of zincoxide, a titanium nitride film, a chromium film, a tungsten film, a Znfilm, or a Pt film. When the first electrode 613 has a stackedstructure, the first electrode 613 shows low resistance enough to serveas a wiring, giving an good ohmic contact, and can function as an anode.

In addition, the layer 616 including a light emitting substance isformed by various methods such as an evaporation method using anevaporation mask, an ink-jet method, and a spin coating method. Thelayer 616 including a light emitting substance has the anthracenederivative of the present invention described in Embodiment Mode 1.Further, the layer 616 including a light emitting substance may beformed using another material including a low molecular compound or ahigh molecular compound (including oligomer and dendrimer). As amaterial used for the EL layer, not only an organic compound but also aninorganic compound may be used.

As a material used for the second electrode 617, which is formed overthe layer 616 including a light emitting substance and serves as acathode, a material having a low work function (Al, Mg, Li, Ca, or analloy or a compound thereof such as MgAg, MgIn, AlLi, LiF, or CaF₂) ispreferably used. In a case where light generated in the layer 616including a light emitting substance is transmitted through the secondelectrode 617, stacked layers of a metal thin film and a transparentconductive film (ITO, indium oxide including 2 to 20 wt % of zinc oxide,indium oxide-tin oxide including silicon or silicon oxide, zinc oxide(ZnO), or the like) are preferably used as the second electrode 617.

By attachment of the sealing substrate 604 to the element substrate 610with the sealing material 605, a structure where a light emittingelement 618 is provided in the space 607 surrounded by the elementsubstrate 610, the sealing substrate 604, and the sealing material 605is formed. It is to be noted that the space 607 is filled with a filler;there is a case where an inert gas (nitrogen, argon, or the like) isused or a case where the sealing material 605 is used.

It is to be noted that an epoxy-based resin is preferably used as thesealing material 605. It is desired that the material allows as littlemoisture and oxygen as possible to penetrate. As the sealing substrate604, a plastic substrate formed using FRP (Fiberglass-ReinforcedPlastics), PVF (polyvinyl fluoride), polyester, acrylic resin, or thelike can be used as well as a glass substrate or a quartz substrate.

By the above-described process, a light emitting device having theanthracene derivative of the present invention can be obtained.

Since the anthracene derivative described in Embodiment Mode 1 is usedfor the light emitting device of the present invention, the lightemitting device can have favorable characteristics. Specifically, alight emitting device capable of light emission with a high luminousefficiency can be obtained.

Further, since the anthracene derivative of the present invention has ahigh luminous efficiency, a light emitting device with low powerconsumption can be obtained.

As described above, in this embodiment mode, an active matrix type lightemitting device in which driving of a light emitting element iscontrolled by a transistor is described. Alternatively, a passive matrixtype light emitting device may also be used. FIG. 5 shows a perspectiveview of a passive matrix type light emitting device which ismanufactured by applying the present invention. In FIG. 5, a layer 955including a light emitting substance is provided between an electrode952 and an electrode 956 over a substrate 951. An end portion of theelectrode 952 is covered with an insulating layer 953. Then, a partitionlayer 954 is provided over the insulating layer 953. A side wall of thepartition layer 954 slopes so that a distance between one side wall andthe other side wall becomes narrow toward a substrate surface. In otherwords, a cross section of the partition layer 954 in the direction of ashort side is trapezoidal, and a base (a side extending in a similardirection as a plane direction of the insulating layer 953 and incontact with the insulating layer 953) is shorter than an upper side (aside extending in a similar direction as the plane direction of theinsulating layer 953 and not in contact with the insulating layer 953).The partition layer 954 provided in this manner can prevent a defect ofthe light emitting element owing to static electricity or the like. Alight emitting device with a long lifetime can be obtained in the casewhere the light emitting device is passive matrix type by using thelight emitting element of the present invention. Further, a lightemitting device with low power consumption can be obtained.

Embodiment Mode 8

In Embodiment Mode 8, an electronic device of the present inventionincluding the light emitting device described in Embodiment Mode 7 willbe described. The electronic device of the present invention includesthe anthracene derivative described in Embodiment Mode 1, and has adisplay portion with a long lifetime. Also, the electronic device of thepresent invention possesses a display portion with reduced powerconsumption.

As an electronic device including a light emitting element manufacturedusing the anthracene derivative of the present invention, a camera suchas a video camera or a digital camera, a goggle type display, anavigation system, an audio reproducing device (car audio componentstereo, audio component stereo, or the like), a computer, a gamemachine, a portable information terminal (mobile computer, mobile phone,portable game machine, electronic book, or the like), and an imagereproducing device provided with a recording medium (specifically, adevice capable of reproducing a recording medium such as a DigitalVersatile Disc (DVD) and provided with a display device that can displaythe image), and the like are given. Specific examples of theseelectronic devices are shown in FIGS. 6A to 6D.

FIG. 6A shows a television device according to the present invention,which includes a housing 9101, a supporting base 9102, a display portion9103, speaker portions 9104, a video input terminal 9105, and the like.In the television device, the display portion 9103 has light emittingelements similar to those described in Embodiment Modes 2 to 5, and thelight emitting elements are arranged in matrix. The features of thelight emitting element are exemplified by a high luminous efficiency anda low driving voltage. The light emitting element also has a feature ofexcellent heat resistance. The display portion 9103 which includes thelight emitting element has similar features. Therefore, in thetelevision device, image quality is scarcely deteriorated and lightemission with a high luminance and low power consumption are achieved.Therefore, deterioration compensation function circuits and power supplycircuits can be significantly reduced or downsized in the televisiondevice, which enables reduction in size and weight of the housing 9101and the supporting base 9102. In the television device according to thepresent invention, low power consumption, high image quality, andreduction in size and weight are achieved; therefore, a product which issuitable for living environment can be provided. Further, since theanthracene derivative described in Embodiment Mode 1 is capable of greenlight emission, a full-color display is possible, and a televisiondevice having a display portion with a long life can be obtained.

FIG. 6B shows a computer according to the present invention, whichincludes a main body 9201, a housing 9202, a display portion 9203, akeyboard 9204, an external connection port 9205, a pointing device 9206,and the like. In the computer, the display portion 9203 has lightemitting elements similar to those described in Embodiment Modes 2 to 5,and the light emitting elements are arranged in matrix. The features ofthe light emitting element are a high luminous efficiency and a lowdriving voltage. In addition, the light emitting element also has afeature of excellent heat resistance. The display portion 9203 whichincludes the light emitting element has similar features. Therefore, inthe computer, image quality is scarcely deteriorated and light emissionwith a high luminance and low power consumption are achieved. Due tothese features, deterioration compensation function circuits and powersupply circuits can be significantly reduced or downsized in thecomputer; therefore, reduction in size and weight of the main body 9201and the housing 9202 can be achieved. In the computer according to thepresent invention, low power consumption, high image quality, andreduction in size and weight are achieved; therefore, a product which issuitable for the environment can be provided. Further, since theanthracene derivative described in Embodiment Mode 1 is capable of greenlight emission, a full-color display is possible, and a computer havinga display portion with a long lifetime can be obtained.

FIG. 6C shows a mobile phone according to the present invention, whichincludes a main body 9401, a housing 9402, a display portion 9403, anaudio input portion 9404, an audio output portion 9405, an operation key9406, an external connection port 9407, an antenna 9408, and the like.In the mobile phone, the display portion 9403 has light emittingelements similar to those described in Embodiment Modes 2 to 5, and thelight emitting elements are arranged in matrix. The features of thelight emitting element are exemplified by a high luminous efficiency anda low driving voltage. The light emitting element also has a feature ofexcellent heat resistance. The display portion 9403 which includes thelight emitting element has similar features. Therefore, in the mobilephone, image quality is scarcely deteriorated and light emission with ahigh luminance and low power consumption are achieved. Owing to thesefeatures, deterioration compensation function circuits and power supplycircuits can be significantly reduced or downsized in the mobile phone;therefore, reduction in size and weight of the main body 9401 and thehousing 9402 can be achieved. In the mobile phone according to thepresent invention, low power consumption, high image quality, andreduction in size and weight are achieved; therefore, a product which issuitable for carrying can be provided. Further, since the anthracenederivative described in Embodiment Mode 1 is capable of green lightemission, a full-color display is possible, and a mobile phone having adisplay portion with a long lifetime can be obtained.

FIG. 6D shows a camera according to the present invention, whichincludes a main body 9501, a display portion 9502, a housing 9503, anexternal connection port 9504, a remote control receiving portion 9505,an image receiving portion 9506, a battery 9507, an audio input portion9508, operation keys 9509, an eye piece portion 9510, and the like. Inthe camera, the display portion 9502 has light emitting elements similarto those described in Embodiment Modes 2 to 5, and the light emittingelements are arranged in matrix. The features of the light emittingelement are a high luminous efficiency and a low driving voltage. Thelight emitting element also has a feature of excellent heat resistance.The display portion 9502 which includes the light emitting element hassimilar features. Therefore, in the camera, image quality is scarcelydeteriorated and light emission with a high luminance and lower powerconsumption can be achieved. Owing to these features, deteriorationcompensation function circuits and power supply circuits can besignificantly reduced or downsized in the camera; therefore, reductionin size and weight of the main body 9501 can be achieved. In the cameraaccording to the present invention, low power consumption, high imagequality, and reduction in size and weight are achieved; therefore, aproduct which is suitable for carrying can be provided. Further, theanthracene derivative described in Embodiment Mode 1 is capable of greenlight emission, full-color display is possible, and a camera having adisplay portion with a long lifetime can be obtained.

As described above, the applicable range of the light emitting device ofthe present invention is so wide that the light emitting device can beapplied to electronic devices in various fields. By using the anthracenederivative of the present invention, an electronic device having adisplay portion with reduced power consumption can be provided. Further,an electronic device having a display portion with excellent heatresistance can be provided.

The light emitting device of the present invention can also be used as alighting device. One mode using the light emitting element of thepresent invention as a lighting device will be described with referenceto FIG. 7.

FIG. 7 shows an example of a liquid crystal display device using thelight emitting device of the present invention as a backlight. Theliquid crystal display device shown in FIG. 7 includes a housing 901, aliquid crystal layer 902, a backlight 903, and a housing 904, and theliquid crystal layer 902 is connected to a driver IC 905. The lightemitting device of the present invention is used for the backlight 903,and current is supplied through a terminal 906.

By using the light emitting device of the present invention as thebacklight of the liquid crystal display device, a backlight with reducedpower consumption and a high luminous efficiency can be obtained. Thelight emitting device of the present invention is a lighting device withplane light emission, and can have a large area. Therefore, thebacklight can have a large area, and a liquid crystal display devicehaving a large area can be obtained. Furthermore, the light emittingdevice of the present invention has a thin shape and has low powerconsumption; therefore, a display device with a thin shape and low powerconsumption can also be achieved. Since the light emitting device of thepresent invention has excellent heat resistance, a liquid crystaldisplay device using the light emitting device of the present inventionalso has excellent heat resistance. Further, since the light emittingdevice of the present invention is capable of light emission with a highluminance, a liquid crystal display device using the light emittingdevice of the present invention is also capable of light emission with ahigh luminance.

FIG. 8 shows an example where the light emitting device to which thepresent invention is applied is used as a table lamp, which is alighting device. A table lamp shown in FIG. 8 has a housing 2001 and alight source 2002, and the light emitting device of the presentinvention is used as the light source 2002. The light emitting device ofthe present invention has a high luminous efficiency and low powerconsumption; therefore, a table lamp also has a high luminous efficiencyand low power consumption.

FIG. 9 shows an example where a light emitting device to which thepresent invention is applied is used as an indoor lighting device 3001.Since the light emitting device of the present invention can have alarge area, the light emitting device of the present invention can beused as a lighting device having a large area. Further, the lightemitting device of the present invention has a thin shape and consumeslow power; therefore, the light emitting device of the present inventioncan be used as a lighting device having a thin shape and low powerconsumption. A television device 3002 according to the present inventionas explained in FIG. 6A can be placed in a room where the light emittingdevice manufactured by the present invention is used as the indoorlighting device 3001, and public broadcasting and movies can be watched.In such a case, since both of the devices consume low power, a powerfulimage can be watched in a bright room without concern about electricitycharges.

Example 1

Example 1 will specifically describe a synthetic method of9-[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]-10-phenylanthracene(abbreviation: PCAPhA), which is an anthracene derivative of the presentinvention represented by Structural Formula (201).

[Step 1] Synthesis of N,9-diphenyl-9H-carbazol-3-amine (abbreviation:PCA) (i) Synthesis of 3-bromo-9-phenylcarbazole

A synthetic scheme of 3-bromo-9-phenylcarbazole is shown in (B-1).

24.3 g (100 mmol) of 9-phenylcarbazole was put into a 2 L Meyer flask,and dissolved in 600 mL of glacial acetic acid. Then, 17.8 g (100 mmol)of N-bromosuccinimide was slowly added thereto, and the solution wasstirred for about 12 hours at room temperature. This glacial acetic acidsolution was dropped into 1 L of ice water while being stirred. A whitesolid precipitated was collected by suction filtration, and then washedwith water three times. This solid was dissolved in 150 mL of diethylether, and the solution was washed with a saturated aqueous solution ofsodium bicarbonate and then with water. The organic layer was dried withmagnesium sulfate, the mixture was filtered, and the filtrate wasconcentrated. Thus, an oily substance was obtained. The oily substancewas dissolved in about 50 mL of methanol. A precipitate of a white solidwas produced by keeping this solution still. This solid was collected bysuction filtration and dried. Then, 28.4 g (88% yield) of3-bromo-9-phenylcarbazole was obtained as white powder.

(ii) Synthesis of N,9-diphenyl-9H-carbazol-3-amine (abbreviation: PCA)

A synthetic scheme of N,9-diphenyl-9H-carbazol-3-amine (abbreviation:PCA) is shown in (B-2).

Into a 500 mL three-neck flask were added 19 g (60 mmol) of3-bromo-9-phenylcarbazole, 340 mg (0.6 mmol) ofbis(dibenzylideneacetone)palladium(0), 1.6 g (3.0 mmol) of1,1-bis(diphenylphosphino)ferrocene, and 13 g (180 mmol) ofsodium-tert-butoxide, and the atmosphere in the flask was substituted bynitrogen. Thereafter, 110 mL of dehydrated xylene and 7.0 g (75 mmol) ofaniline were added to the mixture. This mixture was heated and stirredat 90° C. for 7.5 hours under nitrogen. After the reaction wascompleted, about 500 mL of hot toluene was added to the reacted mixture,and this mixture was filtered through Florisil, alumina, and celite. Anoily substance was obtained by concentration of the filtrate, and hexaneand ethyl acetate were added to the substance, which was followed byirradiation with ultrasound. A solid precipitated was collected bysuction filtration and dried to give 15 g (75% yield) ofN-phenyl-(9-phenyl-9H-carbazol-3-yl)amine (abbreviation: PCA) as creamcolored powder. By a nuclear magnetic resonance measurement (NMR), itwas confirmed that this compound was N,9-diphenyl-9H-carbazol-3-amine(abbreviation: PCA).

¹H NMR data of this compound is shown below. ¹H NMR (300 MHz, CDCl₃);6.84 (t, J=6.9 Hz, 1H), 6.97 (d, J=7.8 Hz, 2H), 7.20-7.61 (m, 13H), 7.90(s, 1H), 8.04 (d, J=7.8 Hz, 1H). The ¹H NMR chart is shown in FIGS. 10Aand 10B. Note that the range of 5.0 ppm to 9.0 ppm in FIG. 10A isexpanded and shown in FIG. 10B.

[Step 2] Synthesis of PCAPhA

A synthetic scheme of PCAPhA is shown in (B-3).

Into a 100 mL three-neck flask were added 501 mg (1.5 mmol) of9-bromo-10-phenylanthracene, 504 mg (1.5 mmol) ofN,9-diphenyl-9H-carbazol-3-amine (abbreviation: PCA), and 500 mg (5.2mmol) of sodium-tert-butoxide, and the atmosphere in the flask wassubstituted by nitrogen. Thereafter, 10 mL of toluene and 0.1 mL oftri(tert-butyl)phosphine (10 wt % hexane solution) were added to themixture. This mixture was stirred under reduced atmosphere to bedegassed. After degassing, 43 mg (0.075 mmol) ofbis(dibenzylideneacetone)palladium(0) was added. This mixture wasstirred at 80° C. for 3 hours under nitrogen. After the reaction, themixture was added with about 20 mL of toluene and then washed withwater. An aqueous layer was extracted with toluene, and the extractedsolution was combined with an organic layer and washed with saturatedsaline. The organic layer was dried with magnesium sulfate, this mixturewas naturally filtered, and the filtrate was concentrated. A solidobtained was purified by silica gel column chromatography (developingsolvent; hexane:toluene=7:3). Recrystallization of the obtained solidwith a mixed solvent of chloroform and hexane gave 514 mg of9-[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]-10-phenylanthracene(abbreviation: PCAPhA) as yellow powder in 67% yield.

The absorption spectrum of a toluene solution of PCAPhA is shown in FIG.11. In addition, an absorption spectrum of a thin film of PCAPhA isshown in FIG. 12. An ultraviolet-visible spectrophotometer (type V550,manufactured by Japan Spectroscopy Corporation) was used formeasurement. The solution was put into a quartz cell and the thin filmsample was manufactured by vapor deposition of PCAPhA on a quartzsubstrate. The absorption spectra thereof, from each of which theabsorption spectrum of quartz was subtracted, are shown in FIGS. 11 and12. In each of FIGS. 11 and 12, the horizontal axis shows wavelength(nm) and the vertical axis shows absorption intensity (an arbitraryunit). In the case of the toluene solution, absorption was observed ataround 450 nm, and in the case of the thin film, absorption was observedat around 497 nm. Further, an emission spectrum of the toluene solution(excitation wavelength of 370 nm) of PCAPhA is shown in FIG. 13, and anemission spectrum of the thin film (excitation wavelength of 480 nm) ofPCAPhA is shown in FIG. 14. In each of FIGS. 13 and 14, the horizontalaxis shows wavelength (nm) and the vertical axis shows emissionintensity (an arbitrary unit). In the case of the toluene solution, themaximum light emission wavelength was 552 nm (excitation wavelength of370 nm), and in the case of the thin film, the maximum emissionwavelength was 574 nm (excitation wavelength of 480 nm).

The HOMO level of PCAPhA in a thin film state which was measured by aphotoelectron spectrometer (AC-2, manufactured by Riken Keiki Co., Ltd.)under air was −5.33 eV. By the absorption edge obtained from a Tauc plotof the absorption spectrum of the thin film of PCAPhA shown in FIG. 12,the optical energy gap was estimated to be 2.27 eV, which means thatLUMO level of PCAPhA is −3.06 eV.

An oxidation-reduction characteristic of PCAPhA was measured by a cyclicvoltammetry (CV) measurement. For the measurement, an electrochemicalanalyzer (ALS model 600A, manufactured by BAS Inc.) was used.

As for a solution used in the CV measurement, dehydrateddimethylformamide (DMF) (manufactured by Aldrich, 99.8%, catalog number:22705-6) was used as a solvent. Tetra-n-butylammonium perchlorate(n-Bu₄NClO₄) (manufactured by Tokyo Chemical Industry Co., Ltd., catalognumber: T0836), which is a supporting electrolyte, was dissolved in DMFat a concentration of 100 mmol/L to prepare the electrolysis solution.The sample solution was prepared by dissolving the measurement object inthe electrolysis solution to be at a concentration of 1 mmol/L. Aplatinum electrode (a PTE platinum electrode, manufactured by BAS Inc.)was used as a working electrode. A platinum electrode (a VC-3 Pt counterelectrode (5 cm), manufactured by BAS Inc.) was used as a counterelectrode. An Ag/Ag⁺ electrode (an RE5 non-aqueous solvent typereference electrode, manufactured by BAS Inc.) was used as a referenceelectrode. The measurement was conducted at room temperature.

The oxidation characteristic of PCAPhA was evaluated in the followingmanner. The potential of the working electrode with respect to thereference electrode was shifted from −0.17 V to 0.80 V, which wasfollowed by shifting the potential from 0.80 V to −0.17 V. This cyclewas set as one cycle, and 100 cycles were performed. In addition, thereduction characteristic of PCAPhA was evaluated in the followingmanner. The potential of the working electrode with respect to thereference electrode was shifted from −0.07 V to −2.50 V, which wasfollowed by shifting the potential from −2.50 V to −0.07 V. This cyclewas set as one cycle, and 100 cycles were performed. The scanning rateof the CV measurement was set to be 0.1 V/s.

The CV measurement result of oxidation of PCAPhA and the CV measurementresult of reduction of PCAPhA are shown in FIGS. 15 and 16,respectively. In each of FIGS. 15 and 16, the horizontal axis shows apotential (V) of the working electrode with respect to the referenceelectrode, and the vertical axis shows a current value (μA) that flowedbetween the working electrode and the counter electrode. From FIG. 15, acurrent exhibiting oxidation was observed around 0.53 V (vs. Ag/Ag⁺electrode). From FIG. 16, a current exhibiting reduction was observedaround −2.11 V (vs. Ag/Ag⁺ electrode).

In spite of the fact that as many as 100 cycles of shifting wereperformed, a peak position and a peak intensity of the CV curve scarcelychanged in the oxidation and reductions which reveals that theanthracene derivative of the present invention is extremely stableagainst repetition of oxidation and reduction.

Example 2

Example 2 will specifically describe a synthetic method of9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A), that is an anthracene derivative of the presentinvention represented by Structural Formula (238).

[Step 1] Synthesis of PCA2A

A synthetic scheme of PCA2A is shown in (B-4).

Into a 100 mL three-neck flask were added 835 mg (2.5 mmol) of9,10-dibromoanthracene, 1.7 g (5.0 mmol) ofN,9-diphenyl-9H-carbazol-3-amine (abbreviation: PCA), and 1.0 g (10mmol) of sodium-tert-butoxide, and the atmosphere in the flask wassubstituted by nitrogen. Thereafter, 25 mL of toluene and 0.1 mL oftri(tert-butyl)phosphine (10 wt % hexane solution) were added to themixture. This mixture was stirred under reduced atmosphere to bedegassed. After degassing, 72 mg (0.13 mmol) ofbis(dibenzylideneacetone)palladium(0) was added. This mixture wasstirred at 80° C. for 5 hours under nitrogen. After the reaction, themixture was added with about 20 mL of toluene and then washed withwater. An aqueous layer was extracted with toluene, and the extractedsolution was combined with an organic layer and washed with saturatedsaline. The organic layer was dried with magnesium sulfate, this mixturewas naturally filtered, and the filtrate was concentrated. A solidobtained was purified by silica gel column chromatography (developingsolvent; hexane:toluene=7:3). Recrystallization of the obtained solidwith a mixed solvent of dichloromethane and hexane gave 1.4 g of9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A) as orange powder in 67% yield. By a nuclearmagnetic resonance measurement, it was confirmed that this compound was9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A).

¹H NMR data of this compound is shown below. ¹H NMR (300 MHz, CDCl₃)δ=6.82-6.90 (m, 2H), 7.03-7.21 (m, 10H), 7.28-7.60 (m, 22H), 7.90 (d,J=7.8 Hz, 1H), 7.97 (d, J=7.8 Hz, 1H), 8.02 (d, J=2.4 Hz, 1H), 8.12 (s,1H), 8.32-8.36 (m, 4H). The ¹H NMR chart is shown in FIGS. 17A and 17B.Note that the range of 6.5 ppm to 8.5 ppm in FIG. 17A is expanded andshown in FIG. 17B.

Thermogravimetry-differential thermal analysis (TG-DTA) of PCA2A wascarried out. In measuring, a thermo-gravimetric/differential thermalanalyzer (TG/DTA 320, manufactured by Seiko Instruments Inc.) was used,and the thermophysical properties were evaluated under a nitrogenatmosphere at a rate of temperature rise of 10° C./min. From therelationship between the weight and the temperature (thermogravimetry),the temperature at which the weight is less than or equal to 95% of theweight at the onset of measurement was 367° C. at normal pressure.

The absorption spectrum of a toluene solution of PCA2A is shown in FIG.18. In addition, an absorption spectrum of a thin film of PCA2A is shownin FIG. 19. An ultraviolet-visible spectrophotometer (type V550,manufactured by Japan Spectroscopy Corporation) was used formeasurement. The solution was put into a quartz cell and the thin filmsample was manufactured by vapor deposition of PCA2A on a quartzsubstrate. The absorption spectra thereof, from each of which theabsorption spectrum of quartz was subtracted, are shown in FIGS. 18 and19. In each of FIGS. 18 and 19, the horizontal axis shows wavelength(nm) and the vertical axis shows absorption intensity (an arbitraryunit). In the case of the toluene solution, absorption was observed ataround 484 nm, and in the case of the thin film, absorption was observedat around 461 nm. Further, an emission spectrum of the toluene solution(excitation wavelength of 430 nm) of PCA2A is shown in FIG. 20, and anemission spectrum of the thin film (excitation wavelength of 497 nm) ofPCA2A is shown in FIG. 21. In each of FIGS. 20 and 21, the horizontalaxis shows wavelength (nm) and the vertical axis shows emissionintensity (an arbitrary unit). In the case of the toluene solution, themaximum light emission wavelength was 558 nm (excitation wavelength of430 nm), and in the case of the thin film, the maximum emissionwavelength was 585 nm (excitation wavelength of 497 nm).

The HOMO level of PCA2A in a thin film state which was measured by aphotoelectron spectrometer (AC-2, manufactured by Riken Keiki Co., Ltd.)under air was −5.28 eV. By the absorption edge obtained from a Tauc plotof the absorption spectrum of the thin film of PCA2A shown in FIG. 19,the optical energy gap was estimated to be 2.40 eV, which means thatLUMO level of PCA2A is −2.88 eV.

An oxidation-reduction characteristic of PCA2A was measured by a cyclicvoltammetry (CV) measurement. For the measurement, an electrochemicalanalyzer (ALS model 600A, manufactured by BAS Inc.) was used.

As for a solution used in the CV measurement, dehydrateddimethylformamide (DMF) (manufactured by Aldrich, 99.8%, catalog number:22705-6) was used as a solvent. Tetra-n-butylammonium perchlorate(n-Bu₄NClO₄) (manufactured by Tokyo Chemical Industry Co., Ltd., catalognumber: T0836), which is a supporting electrolyte, was dissolved in DMFat a concentration of 100 mmol/L to prepare the electrolysis solution.The sample solution was prepared by dissolving the measurement object inthe electrolysis solution to be at a concentration of 1 mmol/L. Aplatinum electrode (a PTE platinum electrode, manufactured by BAS Inc.)was used as a working electrode. A platinum electrode (a VC-3 Pt counterelectrode (5 cm), manufactured by BAS Inc.) was used as a counterelectrode. An Ag/Ag⁺ electrode (an RE5 non-aqueous solvent typereference electrode, manufactured by BAS Inc.) was used as a referenceelectrode. The measurement was conducted at room temperature.

The oxidation characteristic of PCA2A was evaluated in the followingmanner. The potential of the working electrode with respect to thereference electrode was shifted from −0.27 V to 0.60 V, which wasfollowed by shifting the potential from 0.60 V to −0.27 V. This cyclewas set as one cycle, and 100 cycles were performed. In addition, thereduction characteristic of PCA2A was evaluated in the following manner.The potential of the working electrode with respect to the referenceelectrode was shifted from −0.19 V to −2.40 V, which was followed byshifting the potential from −2.40 V to −0.19 V. This cycle was set asone cycle, and 100 cycles were performed. The scanning rate of the CVmeasurement was set to be 0.1 V/s.

The CV measurement result of oxidation of PCA2A and the CV measurementresult of reduction of PCA2A are shown in FIGS. 22 and 23, respectively.In each of FIGS. 22 and 23, the horizontal axis shows a potential (V) ofthe working electrode with respect to the reference electrode, and thevertical axis shows a current value (μA) that flowed between the workingelectrode and the counter electrode. From FIG. 22, a current exhibitingoxidation was observed around 0.35 V (vs. Ag/Ag⁺ electrode). From FIG.23, a current exhibiting reduction was observed around −2.08 V (vs.Ag/Ag⁺ electrode).

In spite of the fact that as many as 100 cycles of shifting wereperformed, a peak position and a peak intensity of the CV curve scarcelychanged in the oxidation and reduction, which reveals that theanthracene derivative of the present invention is extremely stableagainst repetition of oxidation and reduction.

Example 3

Example 3 will specifically describe a synthetic method of9-{N-[4-(carbazole-9-yl)phenyl]-N-phenylamino}-10-phenylanthracene(abbreviation: YGAPhA), which is an anthracene derivative of the presentinvention represented by Structural Formula (301).

[Step 1] Synthesis of 4-(carbazole-9-yl)diphenylamine (abbreviation:YGA) (i) Synthesis of N-(4-bromophenyl)carbazole

A synthetic scheme of N-(4-bromophenyl)carbazole is shown in (B-5).

First, a synthetic method of N-(4-bromophenyl)carbazole is described.56.3 g (0.24 mol) of 1,4-dibromobenzene, 31.3 g (0.18 mol) of carbazole,4.6 g (0.024 mol) of copper(I) iodide, 66.3 g (0.48 mol) of potassiumcarbonate, and 2.1 g (0.008 mol) of 18-crown-6-ether were put into a 300mL three-neck flask, and the atmosphere in the flask was substituted bynitrogen. Thereafter, 8 mL of1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (abbreviation: DMPU)was added to the mixture, and then the mixture was stirred at 180° C.for 6 hours. After the reaction mixture was cooled to room temperature,the precipitate was removed by suction filtration. The filtrate waswashed with a diluted hydrochloric acid, a saturated sodium bicarbonateaqueous solution, and then saturated saline, and dried with magnesiumsulfate. After drying, the mixture was filtered naturally, and thefiltrate was concentrated to yield an oily substance. The oily substancewas purified by silica gel column chromatography (developing solvent;hexane:ethyl acetate=9:1). The resulting solid was recrystallized with amixed solvent of chloroform and hexane, obtaining 20.7 g ofN-(4-bromophenyl)carbazole, which is the object substance, as a lightbrown plate-like crystal in 35% yield. By the nuclear magnetic resonancemeasurement (NMR), it was confirmed that this compound wasN-(4-bromophenyl)carbazole.

¹H NMR data of this compound is shown below. ¹H NMR (300 MHz, CDCl₃):δ=8.14 (d, J=7.8 Hz, 2H), 7.73 (d, J=8.7 Hz, 2H), 7.46 (d, J=8.4 Hz,2H), 7.42-7.26 (m, 6H).

(ii) Synthesis of 4-(carbazol-9-yl)diphenylamine (abbreviation: YGA)

A synthetic scheme of 4-(carbazol-9-yl)diphenylamine (abbreviation: YGA)is shown in (B-6).

5.4 g (17.0 mmol) of N-(4-bromophenyl)carbazole obtained in theabove-mentioned step (i), 1.8 mL (20.0 mmol) of aniline, 100 mg (0.17mmol) of bis(dibenzylideneacetone)palladium(0), and 3.9 g (40 mmol) ofsodium-tert-butoxide were put into a 200 mL three-neck flask, and theatmosphere in the flask was substituted by nitrogen. Thereafter, 0.1 mLof tri-(tert-butyl)phosphine (10 wt % hexane solution) and 50 mL oftoluene were added to the flask, and the solution was stirred at 80° C.for 6 hours. The reaction mixture was filtered through Florisil, celite,and then alumina. The filtrate was washed with water, and then saturatedbrine, and dried with magnesium sulfate. The mixture was filterednaturally, and the filtrate was concentrated to obtain an oilysubstance. The oily substance was purified by silica gel columnchromatography (developing solvent; hexane:ethyl acetate=9:1). Then, 4.1g of 4-(carbazol-9-yl)diphenylamine (abbreviation: YGA), which is theobject substance, was obtained in 73% yield. It was confirmed by anuclear magnetic resonance measurement (NMR) that this compound was4-(carbazol-9-yl)diphenylamine (abbreviation: YGA).

¹H NMR data of this compound is shown below. ¹H NMR (300 MHz, DMSO-d₆):δ=8.47 (s, 1H), 8.22 (d, J=7.8 Hz, 2H), 7.44-7.16 (m, 14H), 6.92-6.87(m, 1H). FIGS. 24A and 24B each show a ¹H NMR chart. Note that the rangeof 6.70 ppm to 8.60 ppm in FIG. 24A is expanded and shown in FIG. 24B.

[Step 2] Synthesis of YGAPhA

A synthetic scheme of YGAPhA is shown in (B-7).

Into a 100 mL three-neck flask were added 2.0 g (6.0 mmol) of9-bromo-10-phenylanthracene, 2.4 g (7.2 mmol) of4-(carbazol-9-yl)diphenylamine (abbreviation: YGA), 0.17 g (0.30 mmol)of bis(dibenzylideneacetone)palladium(0), and 2.9 g (30 mmol) ofsodium-tert-butoxide, and the atmosphere in the flask was substituted bynitrogen. Thereafter, 20 mL of toluene and 0.61 g (0.30 mmol) oftri(tert-butyl)phosphine (10 wt % hexane solution) were added to themixture. This mixture was stirred at 80° C. for 13 hours. After thereaction, the mixture was washed with water. An aqueous layer wasextracted with ethyl acetate, and the extracted solution was combinedwith an organic layer and dried with magnesium sulfate. After drying,the mixture was subjected to suction filtration, and the filtrate wasconcentrated. A residue obtained was dissolved in toluene and thissolution was filtered through Florisil, celite, and alumina by suctionfiltration. The filtrate was concentrated to obtain a solid.Recrystallization of the solid with chloroform and hexane gave 3.2 g of9-{N-[4-(carbazol-9-yl)phenyl]-N-phenylamino}-10-phenylanthracene(abbreviation: YGAPhA), that is the object substance, as yellow powderin 91% yield.

¹H NMR data of this compound is shown below. ¹H NMR (300 MHz, CDCl₃);δ=7.21-7.39 (m, 17H), 7.45-7.53 (m, 4H), 7.57-7.63 (m, 3H), 7.74-7.77(m, 2H), 8.10-8.13 (m, 2H), 8.27-8.30 (m, 2H). The ¹H NMR chart is shownin FIGS. 25A and 25B. Note that the range of 6.5 ppm to 8.5 ppm in FIG.25A is expanded and shown in FIG. 25B.

Thermogravimetry-differential thermal analysis (TG-DTA) of YGAPhA wascarried out. In measuring, a thermo-gravimetric/differential thermalanalyzer (TG/DTA 320, manufactured by Seiko Instruments Inc.) was used,and the thermophysical properties were evaluated under a nitrogenatmosphere at a rate of temperature rise of 10° C./min. From therelationship between the weight and the temperature (thermogravimetry),the temperature at which the weight is less than or equal to 95% of theweight at the onset of measurement was 404° C. at normal pressure, andthis shows YGAPhA has favorable heat resistance.

The absorption spectrum of a toluene solution of YGAPhA is shown in FIG.26. In addition, an absorption spectrum of a thin film of YGAPhA isshown in FIG. 27. An ultraviolet-visible spectrophotometer (type V550,manufactured by Japan Spectroscopy Corporation) was used formeasurement. The solution was put into a quartz cell and the thin filmsample was manufactured by vapor deposition of YGAPhA on a quartzsubstrate. The absorption spectra thereof, from each of which theabsorption spectrum of quartz was subtracted, are shown in FIGS. 26 and27. In each of FIGS. 26 and 27, the horizontal axis shows wavelength(nm) and the vertical axis shows absorption intensity (an arbitraryunit). In the case of the toluene solution, absorption was observed ataround 430 nm, and in the case of the thin film, absorption was observedat around 436 nm. Further, an emission spectrum of the toluene solution(excitation wavelength of 430 nm) of YGAPhA is shown in FIG. 28, and anemission spectrum of the thin film (excitation wavelength of 497 nm) ofYGAPhA is shown in FIG. 29. In each of FIGS. 28 and 29, the horizontalaxis shows wavelength (nm) and the vertical axis shows emissionintensity (an arbitrary unit). In the case of the toluene solution, themaximum light emission wavelength was 510 nm (excitation wavelength of430 nm), and in the case of the thin film, the maximum emissionwavelength was 520 nm (excitation wavelength of 497 nm).

The HOMO level of YGAPhA in a thin film state which was measured by aphotoelectron spectrometer (AC-2, manufactured by Riken Keiki Co., Ltd.)under air was −5.49 eV. By the absorption edge obtained from a Tauc plotof the absorption spectrum of the thin film of YGAPhA shown in FIG. 27,the optical energy gap was estimated to be 2.60 eV, which means thatLUMO level of YGAPhA is −2.89 eV.

Example 4

Example 4 will specifically describe a synthetic method of9,10-bis[N-(4-carbazol-9-yl)phenyl-N-phenylamino]anthracene(abbreviation: YGA2A), which is an anthracene derivative of the presentinvention represented by Structural Formula (335).

[Step 1] Synthesis of YGA2A

A synthetic scheme of YGA2A is shown in (B-8).

Into a 100 mL three-neck flask were added 2.0 g (6.0 mmol) of9,10-dibromoanthracene, 4.4 g (13 mmol) of4-(carbazole-9-yl)diphenylamine (abbreviation: YGA), 0.17 g (0.30 mmol)of bis(dibenzylideneacetone)palladium(0), and 2.9 g (30 mmol) ofsodium-tert-butoxide, and the atmosphere in the flask was substituted bynitrogen. 20 mL of toluene and 0.60 g (0.30 mmol) oftri(tert-butyl)phosphine (10 wt % hexane solution) were added to themixture. This mixture was stirred at 80° C. for 10 hours. After thereaction was completed, the solution was washed with water, and aprecipitate in the solution was collected by suction filtration. Thesolid obtained was dissolved in chloroform and filtered throughFlorisil, celite, and alumina by suction filtration. The filtrate wasconcentrated, and a solid obtained was recrystallized with a mixedsolvent of chloroform and hexane to give 3.9 g of9,10-bis[N-(4-carbazol-9-yl)phenyl-N-phenylamino]anthracene(abbreviation: YGA2A), which is the object substance, as yellow coloredpowder in 79% yield.

¹H NMR data of this compound is shown below. ¹H NMR (300 MHz, CDCl₃);δ=6.99-7.00 (m, 2H), 7.21-7.41 (m, 28H), 7.49-7.52 (m, 4H), 8.09-8.14(m, 4H), 8.32-8.35 (m, 4H). The ¹H NMR chart is shown in FIGS. 30A and30B. Note that the range of 6.5 ppm to 8.5 ppm in FIG. 30A is expandedand shown in FIG. 30B.

Thermogravimetry-differential thermal analysis (TG-DTA) of YGA2A wascarried out. In measuring, a thermo-gravimetric/differential thermalanalyzer (TG/DTA 320, manufactured by Seiko Instruments Inc.) was used,and the thermophysical properties were evaluated under a nitrogenatmosphere at a rate of temperature rise of 10° C./min. From therelationship between the weight and the temperature (thermogravimetry),the temperature at which the weight is less than or equal to 95% of theweight at the onset of measurement was 478.1° C. at normal pressure, andthis shows YGA2A has favorable heat resistance.

The absorption spectrum of a toluene solution of YGA2A is shown in FIG.31. In addition, an absorption spectrum of a thin film of YGA2A is shownin FIG. 32. An ultraviolet-visible spectrophotometer (type V550,manufactured by Japan Spectroscopy Corporation) was used formeasurement. The solution was put into a quartz cell and the thin filmsample was manufactured by vapor deposition of YGA2A on a quartzsubstrate. The absorption spectra thereof, from each of which theabsorption spectrum of quartz was subtracted, are shown in FIGS. 31 and32. In each of FIGS. 31 and 32, the horizontal axis shows wavelength(nm) and the vertical axis shows absorption intensity (an arbitraryunit). In the case of the toluene solution, absorption was observed ataround 463 nm, and in the case of the thin film, absorption was observedat around 470 nm. Further, an emission spectrum of the toluene solution(excitation wavelength of 461 nm) of YGA2A is shown in FIG. 33, and anemission spectrum of the thin film (excitation wavelength of 450 nm) ofYGA2A is shown in FIG. 34. In each of FIGS. 33 and 34, the horizontalaxis shows wavelength (nm) and the vertical axis shows emissionintensity (an arbitrary unit). In the case of the toluene solution, themaximum light emission wavelength was 526 nm (excitation wavelength of461 nm), and in the case of the thin film, the maximum emissionwavelength was 552 nm (excitation wavelength of 450 nm).

The HOMO level of YGA2A in a thin film state which was measured by aphotoelectron spectrometer (AC-2, manufactured by Riken Keiki Co., Ltd.)under air was −5.37 eV. By the absorption edge obtained from a Tauc plotof the absorption spectrum of the thin film of YGA2A shown in FIG. 32,the optical energy gap was estimated to be 2.40 eV, which means thatLUMO level of YGA2A is −2.97 eV.

Example 5

Example 5 will describe a light emitting element of the presentinvention with reference to FIG. 35. Structural formulae of materialsused in Examples 5 to 8 are shown below.

Hereinafter, a manufacturing method of a light emitting element of thisexample is described.

First, a film of indium tin oxide containing silicon oxide (ITSO) wasformed by a sputtering method over a glass substrate 2101 to form afirst electrode 2102. Note that the film thickness of the firstelectrode 2102 was 110 nm, and the area of the electrode was 2 mm×2 mm.

Next, the substrate over which the first electrode 2102 was formed wasfixed to a substrate holder provided in a vacuum evaporation apparatusso that a surface of the substrate over which the first electrode 2102was formed faced down. Then, after reducing the pressure of the vacuumevaporation apparatus to about 10⁻⁴ Pa, a layer 2103 containing acomposite material of an organic compound and an inorganic compound wasformed on the first electrode 2102 by co-evaporating4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) andmolybdenum(VI) oxide. The film thickness of the layer 2103 was to be 50nm, and the weight ratio of NPB and molybdenum(VI) oxide was adjusted tobe 4:1 (=NPB:molybdenum oxide). Note that the co-evaporation method isan evaporation method in which evaporation is carried out from aplurality of evaporation sources at the same time in one treatmentchamber.

Then, a film of 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl(abbreviation: NPB) was formed at a thickness of 10 nm on the layer 2103containing the composite material by the evaporation method usingresistance heating, thereby forming a hole transporting layer 2104.

Further, by co-evaporating 9,10-di(2-naphthyl)-2-tert-butylanthracene(abbreviation: t-BuDNA) and9-[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]-10-phenylanthracene(abbreviation: PCAPhA) represented by Structural Formula (201), a lightemitting layer 2105 with a thickness of 40 nm was formed on the holetransporting layer 2104. The weight ratio of t-BuDNA and PCAPhA wasadjusted to be 1:0.2 (=t-BuDNA:PCAPhA).

Thereafter, tris(8-quinolinolato)aluminum (abbreviation: Alq) was formedat a film thickness of 30 nm on the light emitting layer 2105 by meansof the evaporation method using resistance heating, resulting in theformation of an electron transporting layer 2106.

Furthermore, a film of lithium fluoride (LiF) was formed at a thicknessof 1 nm on the electron transporting layer 2106 to form an electroninjecting layer 2107.

Lastly, by forming a film of aluminum with a film thickness of 200 nm onthe electron injecting layer 2107 by means of the evaporation methodusing resistance heating, a second electrode 2108 was formed. Thus, alight emitting element 1 was manufactured.

A luminance-current density characteristic, a luminance-voltagecharacteristic, and a current efficiency-luminance characteristic of thelight emitting element 1 are shown in FIGS. 36, 37, and 38,respectively. Also, the emission spectrum which was obtained at acurrent of 1 mA is illustrated in FIG. 39. The CIE chromaticitycoordinates of the light emitting element 1 at a luminance of 990 cd/m²was (x=0.41, y=0.56), and light emission was yellow green. At aluminance of 990 cd/m², the current efficiency was 13 cd/A and theexternal quantum efficiency was 3.9%, meaning that high currentefficiency and high external quantum efficiency were exhibited. Inaddition, at a luminance of 990 cd/m², the voltage was 5.2 V, thecurrent density was 7.7 mA/cm², and the power efficiency was 7.7 (1m/W). As shown in FIG. 39, the maximum emission wavelength at a currentof 1 mA was 546 nm.

Example 6

Example 6 will describe a light emitting element of the presentinvention with reference to FIG. 35. A manufacturing method of a lightemitting element of this example is described below.

First, a film of indium tin oxide containing silicon oxide (ITSO) wasformed by a sputtering method over a glass substrate 2101 to form afirst electrode 2102. Note that the film thickness of the firstelectrode 2102 was 110 nm, and the area of the electrode was 2 mm×2 mm.

Next, the substrate over which the first electrode 2102 was formed wasfixed to a substrate holder provided in a vacuum evaporation apparatusso that a surface of the substrate over which the first electrode 2102was formed faced down. Then, after reducing the pressure of the vacuumevaporation apparatus to about 10⁻⁴ Pa, a layer 2103 containing acomposite material of an organic compound and an inorganic compound wasformed on the first electrode 2102 by co-evaporating4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) andmolybdenum(VI) oxide. The film thickness of the layer 2103 was to be 50nm, and the weight ratio of NPB and molybdenum(VI) oxide was adjusted tobe 4:1 (=NPB:molybdenum oxide). Note that the co-evaporation method isan evaporation method in which evaporation is carried out from aplurality of evaporation sources at the same time in one treatmentchamber.

Then, a film of 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl(abbreviation: NPB) was formed at a thickness of 10 nm on the layer 2103containing the composite material by the evaporation method usingresistance heating, thereby forming a hole transporting layer 2104.

Further, by co-evaporating9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA) and9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A) represented by Structural Formula (238), a lightemitting layer 2105 with a thickness of 40 nm was formed on the holetransporting layer 2104. The weight ratio of CzPA and PCA2A in the lightemitting element 2 was adjusted to be 1:0.05 (=CzPA:PCA2A), and theweight ratio in the light emitting element 3 was adjusted to be 1:0.2(=CzPA:PCA2A).

Thereafter, tris(8-quinolinolato)aluminum (abbreviation: Alq) was formedat a film thickness of 30 nm on the light emitting layer 2105 by meansof the evaporation method using resistance heating, resulting in theformation of an electron transporting layer 2106.

Furthermore, a film of lithium fluoride (LiF) was formed at a thicknessof 1 nm on the electron transporting layer 2106 to form an electroninjecting layer 2107.

Lastly, by forming a film of aluminum with a film thickness of 200 nm onthe electron injecting layer 2107 by means of the evaporation methodusing resistance heating, a second electrode 2108 was formed. Thus, alight emitting element 2 and a light emitting element 3 weremanufactured.

Luminance-current density characteristics, luminance-voltagecharacteristics, and current efficiency-luminance characteristics of thelight emitting element 2 and the light emitting element 3 are shown inFIGS. 40, 41, and 42, respectively. Also, the emission spectrum whichwas obtained at a current of 1 mA is illustrated in FIG. 43. The CIEchromaticity coordinates of the light emitting element 2 at a luminanceof 980 cd/m² was (x=0.48, y=0.52), and light emission was yellow. At aluminance of 980 cd/m², the current efficiency was 16 cd/A and theexternal quantum efficiency was 5.6%, meaning that high currentefficiency and high external quantum efficiency were exhibited. Inaddition, at a luminance of 980 cd/m², the voltage was 6.8 V, thecurrent density was 6.3 mA/cm², and the power efficiency was 7.1 (1m/W). As shown in FIG. 43, the maximum emission wavelength at a currentof 1 mA was 583 nm. The CIE chromaticity coordinates of the lightemitting element 3 at a luminance of 900 cd/m² was (x=0.50, y=0.50), andlight emission was yellow. At a luminance of 900 cd/m², the currentefficiency was 18 cd/A and the external quantum efficiency was 5.8%,meaning that high current efficiency and high external quantumefficiency were exhibited. In addition, at a luminance of 900 cd/m², thevoltage was 5.4 V, the current density was 5.0 mA/cm², and the powerefficiency was 10 (1 m/W). As shown in FIG. 43, the maximum emissionwavelength at a current of 1 mA was 565 nm.

Seen in FIGS. 40 to 43, the light emitting element 3 has a much highercurrent efficiency than the light emitting element 2. In addition, thelight emitting element 3 has a lower driving voltage than the lightemitting element 2, which means the light emitting element 3 has lesspower consumption.

A continuous lighting test was conducted on the light emitting element 2by constant current driving at an initial luminance of 3000 cd/m². FIG.44 shows the result, where time dependence of normalized luminance atthe time when initial luminance is considered to be 100% is shown. FromFIG. 44, it is seen that the light emitting element 2 maintains 76% ofthe initial luminance even after 1400 hours, and this shows the lightemitting element 2 has a long lifetime. Accordingly, by using ananthracene derivative of the present invention, a long-life lightemitting element can be obtained. In particular, when9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A) represented by Structural Formula (238) is used, along-life light emitting element can be obtained. Compounds having apartial structure of N,9-diphenyl-9H-carbazol-3-amine (abbreviation:PCA) are extremely stable against repetition of oxidation and reduction.By provision of a substituent at position 9 and position 10 ofanthracene, the value of HOMO level can become an appropriate value fora light emitting layer. Accordingly, PCA2A used in this example ispreferable for light emitting elements.

Example 7

Example 7 will describe a light emitting element of the presentinvention with reference to FIG. 35. A manufacturing method of a lightemitting element of this example is described below.

First, a film of indium tin oxide containing silicon oxide (ITSO) wasformed by a sputtering method over a glass substrate 2101 to form afirst electrode 2102. Note that the film thickness of the firstelectrode 2102 was 110 nm, and the area of the electrode was 2 mm×2 mm.

Next, the substrate over which the first electrode 2102 was formed wasfixed to a substrate holder provided in a vacuum evaporation apparatusso that a surface of the substrate over which the first electrode 2102was formed faced down. Then, after reducing the pressure of the vacuumevaporation apparatus to about 10⁻⁴ Pa, a layer 2103 containing acomposite material of an organic compound and an inorganic compound wasformed on the first electrode 2102 by co-evaporating4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) andmolybdenum(VI) oxide. The film thickness of the layer 2103 was to be 50nm, and the weight ratio of NPB and molybdenum(VI) oxide was adjusted tobe 4:1 (=NPB:molybdenum oxide). Note that the co-evaporation method isan evaporation method in which evaporation is carried out from aplurality of evaporation sources at the same time in one treatmentchamber.

Then, a film of 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl(abbreviation: NPB) was formed at a thickness of 10 nm on the layer 2103containing the composite material by the evaporation method usingresistance heating, thereby forming a hole transporting layer 2104.

Further, by co-evaporating tris(8-quinolinolato)aluminum (abbreviation:Alq) and9-{N-[4-(carbazol-9-yl)phenyl]-N-phenylamino}-10-phenylanthracene(abbreviation: YGAPhA), which is an anthracene derivative represented byStructural Formula (301), a light emitting layer 2105 with a thicknessof 40 nm was formed on the hole transporting layer 2104. The weightratio of Alq and YGAPhA was adjusted to be 1:0.5 (=Alq:YGAPhA).

Thereafter, tris(8-quinolinolato)aluminum (abbreviation: Alq) was formedat a film thickness of 30 nm on the light emitting layer 2105 by meansof the evaporation method using resistance heating, resulting in theformation of an electron transporting layer 2106.

Furthermore, a film of lithium fluoride (LiF) was formed at a thicknessof 1 nm on the electron transporting layer 2106 to form an electroninjecting layer 2107.

Lastly, by forming a film of aluminum with a film thickness of 200 nm onthe electron injecting layer 2107 by means of the evaporation methodusing resistance heating, a second electrode 2108 was formed. Thus, alight emitting element 4 was manufactured.

Comparative Example 1

Hereinafter, a method for fabricating a light emitting element of acomparative example is described. A structural formula of a materialused in this comparative example is shown below.

First, a film of indium tin oxide containing silicon oxide (ITSO) wasformed by a sputtering method over a glass substrate to form a firstelectrode. Note that the film thickness of the first electrode was 110nm, and the area of the electrode was 2 mm×2 mm.

Next, the substrate over which the first electrode was formed was fixedto a substrate holder provided in a vacuum evaporation apparatus so thata surface of the substrate over which the first electrode was formedfaced down. Then, after reducing the pressure of the vacuum evaporationapparatus to about 10⁻⁴ Pa, a layer containing a composite material ofan organic compound and an inorganic compound was formed on the firstelectrode by co-evaporating4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) andmolybdenum(VI) oxide. The film thickness of the layer was to be 50 nm,and the weight ratio of NPB and molybdenum(VI) oxide was adjusted to be4:1 (=NPB:molybdenum oxide). Note that the co-evaporation method is anevaporation method in which evaporation is carried out from a pluralityof evaporation sources at the same time in one treatment chamber.

Then, a film of 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl(abbreviation: NPB) was formed at a thickness of 10 nm on the layercontaining the composite material by the evaporation method usingresistance heating, thereby forming a hole transporting layer.

Further, by co-evaporating tris(8-quinolinolato)aluminum (abbreviation:Alq) and 9-diphenylamino-10-phenylanthracene (abbreviation: DPhAPhA), alight emitting layer with a thickness of 40 nm was formed on the holetransporting layer. The weight ratio of Alq and DPhAPhA was adjusted tobe 1:0.5 (=Alq:DPhAPhA).

Thereafter, tris(8-quinolinolato)aluminum (abbreviation: Alq) was formedat a film thickness of 30 nm on the light emitting layer by means of theevaporation method using resistance heating, resulting in the formationof an electron transporting layer.

Furthermore, a film of lithium fluoride (LiF) was formed at a thicknessof 1 nm on the electron transporting layer to form an electron injectinglayer.

Lastly, by forming a film of aluminum with a film thickness of 200 nm onthe electron injecting layer by means of the evaporation method usingresistance heating, a second electrode was formed. Thus, a comparativelight emitting element 5 was manufactured.

Luminance-current density characteristics, luminance-voltagecharacteristics, and current efficiency-luminance characteristics of thelight emitting element 4 and the comparative light emitting element 5are shown in FIGS. 45, 46, and 47, respectively. Also, the emissionspectrum which was obtained at a current of 1 mA is illustrated in FIG.48. The CIE chromaticity coordinates of the light emitting element 4 ata luminance of 1100 cd/m² was (x=0.35, y=0.60), and light emission wasgreen. At a luminance of 1100 cd/m², the current efficiency was 11 cd/Aand the external quantum efficiency was 3.0%, meaning that high currentefficiency and high external quantum efficiency were exhibited. Inaddition, at a luminance of 1100 cd/m², the voltage was 4.0 V, thecurrent density was 11 mA/cm², and the power efficiency was 7.1 (1 m/W).As shown in FIG. 48, the maximum emission wavelength at a current of 1mA was 543 nm.

The CIE chromaticity coordinates of the comparative light emittingelement 5 at a luminance of 870 cd/m² was (x=0.32, y=0.58), and lightemission was green. At a luminance of 870 cd/m², the current efficiencywas 7.9 cd/A and the external quantum efficiency was 2.5%. In addition,at a luminance of 870 cd/m², the voltage was 5.6 V, the current densitywas 11 mA/cm², and the power efficiency was 4.4 (1 m/W). As shown inFIG. 48, the maximum emission wavelength at a current of 1 mA was 517nm.

Seen in FIGS. 45 to 48, the light emitting element 4 has a highercurrent efficiency and a higher external quantum efficiency than thecomparative light emitting element 5. In addition, the light emittingelement 4 has a higher power efficiency than the comparative lightemitting element 5, which means the light emitting element 4 has lesspower consumption. Accordingly, by applying an anthracene derivative ofthe present invention for a light emitting element, a high luminousefficiency can be achieved. In addition, a light emitting element withlow power consumption can be obtained.

Example 8

Example 8 will describe a light emitting element of the presentinvention with reference to FIG. 35. A manufacturing method of a lightemitting element of this example is described below.

First, a film of indium tin oxide containing silicon oxide (ITSO) wasformed by a sputtering method over a glass substrate 2101 to form afirst electrode 2102. Note that the film thickness of the firstelectrode 2102 was 110 nm, and the area of the electrode was 2 mm×2 mm.

Next, the substrate over which the first electrode 2102 was formed wasfixed to a substrate holder provided in a vacuum evaporation apparatusso that a surface of the substrate over which the first electrode 2102was formed faced down. Then, after reducing the pressure of the vacuumevaporation apparatus to about 10⁻⁴ Pa, a layer 2103 containing acomposite material of an organic compound and an inorganic compound wasformed on the first electrode 2102 by co-evaporating4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) andmolybdenum(VI) oxide. The film thickness of the layer 2103 was to be 50nm, and the weight ratio of NPB and molybdenum(VI) oxide was adjusted tobe 4:1 (=NPB:molybdenum oxide). Note that the co-evaporation method isan evaporation method in which evaporation is carried out from aplurality of evaporation sources at the same time in one treatmentchamber.

Then, a film of 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl(abbreviation: NPB) was formed at a thickness of 10 nm on the layer 2103containing the composite material by the evaporation method usingresistance heating, thereby forming a hole transporting layer 2104.

Further, by co-evaporating9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA) and9,10-bis[N-(4-carbazol-9-yl)phenyl-N-phenylamino]anthracene(abbreviation: YGA2A), which is an anthracene derivative represented byStructural Formula (335), a light emitting layer 2105 with a thicknessof 40 nm was formed on the hole transporting layer 2104. The weightratio of CzPA and YGA2A was adjusted to be 1:0.2 (=CzPA:YGA2A).

Thereafter, tris(8-quinolinolato)aluminum (abbreviation: Alq) was formedat a film thickness of 30 nm on the light emitting layer 2105 by meansof the evaporation method using resistance heating, resulting in theformation of an electron transporting layer 2106.

Furthermore, a film of lithium fluoride (LiF) was formed at a thicknessof 1 nm on the electron transporting layer 2106 to form an electroninjecting layer 2107.

Lastly, by forming a film of aluminum with a film thickness of 200 nm onthe electron injecting layer 2107 by means of the evaporation methodusing resistance heating, a second electrode 2108 was formed. Thus, alight emitting element 6 was manufactured.

Comparative Example 2

Hereinafter, a method for fabricating a light emitting element of acomparative example is described. A structural formula of a materialused in this comparative example is shown below.

First, a film of indium tin oxide containing silicon oxide (ITSO) wasformed by a sputtering method over a glass substrate to form a firstelectrode. Note that the film thickness of the first electrode was 110nm, and the area of the electrode was 2 mm×2 mm.

Next, the substrate over which the first electrode was formed was fixedto a substrate holder provided in a vacuum evaporation apparatus so thata surface of the substrate over which the first electrode was formedfaced down. Then, after reducing the pressure of the vacuum evaporationapparatus to about 10⁻⁴ Pa, a layer containing a composite material ofan organic compound and an inorganic compound was formed on the firstelectrode by co-evaporating4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) andmolybdenum(VI) oxide. The film thickness of the layer was to be 50 nm,and the weight ratio of NPB and molybdenum(VI) oxide was adjusted to be4:1 (=NPB:molybdenum oxide). Note that the co-evaporation method is anevaporation method in which evaporation is carried out from a pluralityof evaporation sources at the same time in one treatment chamber.

Then, a film of 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl(abbreviation: NPB) was formed at a thickness of 10 nm on the layercontaining the composite material by the evaporation method usingresistance heating, thereby forming a hole transporting layer.

Further, by co-evaporating9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA) and9,10-bis(diphenylamino)anthracene (abbreviation: DPhA2A), a lightemitting layer with a thickness of 40 nm was formed on the holetransporting layer. The weight ratio of CzPA and DPhA2A was adjusted tobe 1:0.25 (=CzPA:DPhA2A).

Thereafter, tris(8-quinolinolato)aluminum (abbreviation: Alq) was formedat a film thickness of 30 nm on the light emitting layer by means of theevaporation method using resistance heating, resulting in the formationof an electron transporting layer.

Furthermore, a film of lithium fluoride (LiF) was formed at a thicknessof 1 nm on the electron transporting layer to form an electron injectinglayer.

Lastly, by forming a film of aluminum with a film thickness of 200 nm onthe electron injecting layer by means of the evaporation method usingresistance heating, a second electrode was formed. Thus, a comparativelight emitting element 7 was manufactured.

Luminance-current density characteristics, luminance-voltagecharacteristics, and current efficiency-luminance characteristics of thelight emitting element 6 and the comparative light emitting element 7are shown in FIGS. 49, 50, and 51, respectively. Also, the emissionspectrum which was obtained at a current of 1 mA is illustrated in FIG.52. The CIE chromaticity coordinates of the light emitting element 6 ata luminance of 940 cd/m² was (x=0.39, y=0.58), and light emission wasyellow green. At a luminance of 940 cd/m², the current efficiency was 11cd/A and the external quantum efficiency was 3.2%, meaning that highcurrent efficiency and high external quantum efficiency were exhibited.In addition, at a luminance of 940 cd/m², the voltage was 5.6 V, thecurrent density was 8.4 mA/cm², and the power efficiency was 6.3 (1m/W). As shown in FIG. 52, the maximum emission wavelength at a currentof 1 mA was 542 mm.

The CIE chromaticity coordinates of the comparative light emittingelement 7 at a luminance of 750 cd/m² was (x=0.36, y=0.60), and lightemission was yellow green. At a luminance of 750 cd/m², the currentefficiency was 8.9 cd/A and the external quantum efficiency was 2.7%. Inaddition, at a luminance of 750 cd/m², the voltage was 6.0 V, thecurrent density was 8.4 mA/cm², and the power efficiency was 4.6 (1m/W). As shown in FIG. 52, the maximum emission wavelength at a currentof 1 mA was 524 mm.

Seen in FIGS. 49 to 52, the light emitting element 6 has a highercurrent efficiency and a higher external quantum efficiency than thecomparative light emitting element 7. In addition, the light emittingelement 6 has a higher power efficiency than the comparative lightemitting element 7, which means the light emitting element 6 has lesspower consumption. Accordingly, by applying an anthracene derivative ofthe present invention for a light emitting element, a high luminousefficiency can be achieved. In addition, a light emitting element withlow power consumption can be obtained.

Example 9

Example 9 will describe a light emitting element of the presentinvention with reference to FIG. 53. In this example, a light emittingelement exhibiting whitish light emission is manufactured by using ananthracene derivative of the present invention. Structural formulae ofmaterials used in this example are shown below. Note that the structuralformulae of the materials described in Examples 3 to 8 are omitted.

Hereinafter, a manufacturing method of a light emitting element of thisexample is described.

First, a film of indium tin oxide containing silicon oxide (ITSO) wasformed by a sputtering method over a glass substrate 2201 to form afirst electrode 2202. Note that the film thickness of the firstelectrode 2202 was 110 nm, and the area of the electrode was 2 mm×2 mm.

Next, the substrate over which the first electrode 2202 was formed wasfixed to a substrate holder provided in a vacuum evaporation apparatusso that a surface of the substrate over which the first electrode 2202was formed faced down. Then, after reducing the pressure of the vacuumevaporation apparatus to about 10⁻⁴ Pa, a layer 2203 containing acomposite material of an organic compound and an inorganic compound wasformed on the first electrode 2202 by co-evaporating4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) andmolybdenum(VI) oxide. The film thickness of the layer 2203 was to be 50nm, and the weight ratio of NPB and molybdenum(VI) oxide was adjusted tobe 4:1 (=NPB:molybdenum oxide).

Then, a film of 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl(abbreviation: NPB) was formed at a thickness of 10 nm on the layer 2203containing the composite material by the evaporation method usingresistance heating, thereby forming a hole transporting layer 2204.

Further, by co-evaporating4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) and9,10-bis[N-phenyl-N-(9-phenylcarbazol-3-yl)amino]anthracene(abbreviation: PCA2A), which is an anthracene derivative represented byStructural Formula (238), a first light emitting layer 2205 with athickness of 10 nm was formed on the hole transporting layer 2204. Theweight ratio of NPB and PCA2A in the light emitting element 8 wasadjusted to be 1:0.01 (=NPB:PCA2A) and the weight ratio in the lightemitting element 9 was adjusted to be 1:0.005 (=NPB:PCA2A).

Further, by co-evaporating9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA) andN,N′-bis[4-(9H-carbazol-9-yl)phenyl]-N,N′-diphenylstilbene-4,4′-diamine(abbreviation: YGA2S), a second light emitting layer 2206 with athickness of 20 nm was formed on the first light emitting layer 2205.The weight ratio of CzPA and YGA2S was adjusted to be 1:0.04(=CzPA:YGA2S).

Thereafter, bathophenanthroline (abbreviation: Bphen) was formed at afilm thickness of 30 nm on the second light emitting layer 2206 by meansof the evaporation method using resistance heating, resulting in theformation of an electron transporting layer 2207.

Furthermore, a film of lithium fluoride (LiF) was formed at a thicknessof 1 nm on the electron transporting layer 2207 to form an electroninjecting layer 2208.

Lastly, by forming a film of aluminum with a film thickness of 200 nm onthe electron injecting layer 2208 by means of the evaporation methodusing resistance heating, a second electrode 2209 was formed. Thus, alight emitting element 8 and a light emitting element 9 weremanufactured.

Luminance-current density characteristics, luminance-voltagecharacteristics, and current efficiency-luminance characteristics of thelight emitting element 8 and the light emitting element 9 are shown inFIGS. 54, 55, and 56, respectively. Also, the emission spectrum whichwas obtained at a current of 1 mA is illustrated in FIG. 57. The CIEchromaticity coordinates of the light emitting element 8 at a luminanceof 950 cd/m² was (x=0.29, y=0.37), and light emission was white. At aluminance of 950 cd/m², the current efficiency was 13 cd/A, meaning thathigh current efficiency was exhibited. In addition, at a luminance of950 cd/m², the voltage was 3.0 V, the current density was 7.5 mA/cm²,and the power efficiency was 13 (1 m/W), meaning that high powerefficiency was exhibited. As shown in FIG. 57, the light emittingelement 8 exhibits a broad emission spectrum and emits white light withhigh color rendering properties.

The CIE chromaticity coordinates of the light emitting element 9 at aluminance of 1250 cd/m² was (x=0.25, y=0.31), and light emission wasbluish white. At a luminance of 1250 cd/m², the current efficiency was10 cd/A and the external quantum efficiency was 2.7%, meaning that highcurrent efficiency was exhibited. In addition, at a luminance of 1250cd/m², the voltage was 3.0 V, the current density was 12.2 mA/cm², andthe power efficiency was 11 (1 m/W), meaning that high power efficiencywas exhibited. As shown in FIG. 57, the light emitting element 9exhibits a broad emission spectrum and emits white light with high colorrendering properties.

Seen in FIGS. 54 to 57, the light emitting element 8 and the lightemitting element 9 have high current efficiency. It is noticed that theyalso have high power efficiency, meaning they have low powerconsumption. Accordingly, by applying an anthracene derivative of thepresent invention to a light emitting element, a high luminousefficiency can be achieved. In addition, a light emitting element withlow power consumption can be obtained. As is seen from FIG. 57, when ananthracene derivative of the present invention is applied to a whitelight emitting element, the white-light emitting element can have abroad emission spectrum and high color rendering properties. Further, awhite light emitting element with a high luminous efficiency and lowpower consumption can be obtained.

This application is based on Japanese Patent Application serial no.2006-266002 filed in Japan Patent Office on Sep. 28, 2006, the entirecontents of which are hereby incorporated by reference.

1. An anthracene derivative represented by formula (1):

wherein Ar¹ represents a substituent which is represented by formula(11-1), (11-3), (11-4), (11-5), or (11-6),

wherein each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms, wherein each of R¹¹ to R¹⁵ represents any ofa hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an arylgroup having 6 to 15 carbon atoms, wherein each of R¹⁶ and R¹⁷represents an alkyl group having 1 to 4 carbon atoms or a phenyl group,wherein A represents a substituent which is represented by formula(1-3), wherein Ar³¹ represents an aryl group having 6 to 25 carbonatoms, wherein β represents an arylene group having 6 to 25 carbonatoms, and wherein each of R⁴¹ and R⁴² represents any of a hydrogenatom, an alkyl group having 1 to 4 carbon atoms, or an aryl group having6 to 25 carbon atoms.
 2. An anthracene derivative represented by formula(2):

wherein Ar¹ represents a substituent which is represented by generalformula (11-1), (11-3), (11-4), (11-5), or (11-6),

wherein each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms, wherein each of R¹¹ to R¹⁵ represents ahydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an arylgroup having 6 to 15 carbon atoms, wherein each of R¹⁶ and R¹⁷represents an alkyl group having 1 to 4 carbon atoms or a phenyl group,wherein A represents a substituent which is represented by formula(2-3), wherein Ar³¹ represents an aryl group having 6 to 25 carbonatoms, and wherein each of R⁴¹ and R⁴⁶ represents any of a hydrogenatom, an alkyl group having 1 to 4 carbon atoms, or an aryl group having6 to 25 carbon atoms.
 3. The anthracene derivative according to claim 1,wherein Ar³¹ represents a phenyl group, a 1-naphthyl group, or a2-naphthyl group.
 4. The anthracene derivative according to claim 2,wherein Ar³¹ represents a phenyl group, a 1-naphthyl group, or a2-naphthyl group.
 5. An anthracene derivative represented by formula(5):

wherein each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms, wherein A represents a substituent,represented by formula (5-3), wherein Ar³¹ represents an aryl grouphaving 6 to 25 carbon atoms, wherein β represents an arylene grouphaving 6 to 25 carbon atoms, and wherein each of R⁴¹ and R⁴² representsa hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an arylgroup having 6 to 25 carbon atoms.
 6. An anthracene derivativerepresented by formula (6):

wherein each of R¹ to R⁸ represents a hydrogen atom or an alkyl grouphaving 1 to 4 carbon atoms, wherein A represents a substituent, thesubstituent is represented by formula (6-3), wherein Ar³¹ represents anaryl group having 6 to 25 carbon atoms, wherein each of R⁴¹ and R⁴²represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms,or an aryl group having 6 to 25 carbon atoms, and wherein each of R⁴³ toR⁴⁶ represents a hydrogen atom, an alkyl group having 1 to 4 carbonatoms, or an aryl group having 6 to 15 carbon atoms.
 7. The anthracenederivative according to claim 5, wherein Ar³¹ represents a phenyl group,a 1-naphthyl group, or a 2-naphthyl group.
 8. The anthracene derivativeaccording to claim 6, wherein Ar³¹ represents a phenyl group, a1-naphthyl group, or a 2-naphthyl group.
 9. A light emitting elementcomprising the anthracene derivative according to claim 1 between a pairof electrodes.
 10. A light emitting element comprising the anthracenederivative according to claim 2 between a pair of electrodes.
 11. Alight emitting element comprising the anthracene derivative according toclaim 5 between a pair of electrodes.
 12. A light emitting elementcomprising the anthracene derivative according to claim 6 between a pairof electrodes.